Republican leaders and the chairman of the House ethics committee called yesterday for congressional investigations of reports that eight members of Congress face potential bribery charges after being snared in an undercover FBI "sting" operation.

More than 60 GOP officials meeting in Easton, Md., approved a resolution calling for the inquiry and criticizing the Democratic congressional leadership for failing to pursue corruption allegations vigorously.

Rep. Charles E. Bennett (D-Fla.), chairman of the House Committee on Standards of Official Conduct, said in a phone interview that he has asked a Justice Department official to cooperate by handing over some of the evidence uncovered in the FBI's year-and-a-half-long secret operation. Undercover agents posed as Arab sheiks and businessmen, and made video tapes of cash payoffs to some members of New York and Washington.

The Washington Post reported yesterday that the subjects of the investigation include Sen. Harrison A. Williams Jr. (D-N.J.), and Reps. Frank Thompson (D-N.J.), John M. Murphy (D-N.Y.), John W. Jenrette Jr. (D-S.C.), John P. Murtha, Raymond F. Lederer, and Michael Myers, all Pennsylvania Democrats, and Richard Kelly (R-Fla).

Williams, Thompson, Jenrette, Kelly and Murtha hve denied the reports. The others could not be reached for comment.

Several state and local officials, including a New Jersey mayor and gambling commission official, are also said to be under investigation.

FBI agents continued yesterday to question others involved in the "sting" operation, according to sources. Grand juries are expected to be empaneled this week to begin hearing evidence -- and viewing videotapes -- in the case, which is being called the largest Capitol Hill corruption investigation ever.

Federal prosecutors will question witnesses before grand juries in Washington, Philadelphia, Newark and Brooklyn, one source said.

Bennett said that allegations about misconduct by "some of the same members" mentioned in the news accounts already are being checked out by the ethics committee staff. It is known that the committee has been following the progress of federal investigations of Jenrette and Murphy unrelated to the charges arising from the FBI's Arab "sting."

Bennett added that he didn't think the committee would need the videotapes now to conduct its own investiagation of the bribery allegations.

FBI and Justice Department officials continued to refuse to comment officially on the investigation.

But it now seems clear that the undercover agents used several tactics when meeting the members of Congress. The most common was agreeing to exchange cash, usually $50,000, with a members of his associate in return for help in getting an "Arab client" into the United States, according to sources. Other times, some of the House members acknowledged, they were introduced to men representing "Arab businessmen" looking for investments.

In one case last fall, Sen. Larry Pressler (R-S.D.) was introduced to some men who suggested they could raise $50,000 for his presidential race. They also wanted help in getting a "wealthy Arab" into the country. He refused, making him, sources said the only official on the videotapes who is not now a subject of the investigation.

Some of the congressmen were taped and recorded several times, in hotel rooms, and a northwest Washington home that was rented from a Washington Post reporter who wasn't aware of the "sting" operation.

Murphy, for example, was taped last October at the Hilton Inn at Kennedy Airport in New York with Philadelphia attorney Howard Criden, according to souces, discussing how the "client" of the undercover agents could get into the country.

Murphy allegedly suggested the man should buy a house or a company to make it easier, and at the end of the conversation, a closed briefcase filled with $50,000 is offered to the congressmen. But, according to sources, he said, "Howard will take that."

Just a few weeks ago, Murphy was filmed again, in the house in northwest Washington, the sources said. This time he and Criden brought along a businessmen, allegedly for a discussion on how to split up shares of a shipping company the "Arab" might buy.

Murphy, chairman of the House Merchant Marine and Fisheries Committee, reportedly said he'd be glad to show the foreign "sheik" around his office. No money changed hands at that meeting, the sources said.

Murphy and his attorney could not be reached for comment yesterday. He said through an aide Saturday night that he had no idea what the allegations were about.

Murtha was brought to the "sting" agents by Murphy, according to sources, and though he took no money at the taped meeting he is alleged to have said he would take the cash and share it with other members.

Murtha could not be reached for direct comment, but gave a detailed account of his version of the incident to the Greensburg, Pa., Tribune-Review.

Murtha said he had been told by FBI agents who visited him at his Johnston, Pa., home Saturday that he could expect to be called before a grand jury regarding meetings he had with purported representatives of a wealthy citizen of the United Arab Emirates.

"They didn't offer me any money and I didn't take any," the Tribune-Review quoted Murtha as saying.

According to Murtha, he was contacted during the Christmas recess by someone claiming to be a Philadelphia lawyer with an Arab client who wanted to get into the United States as a permanent resident -- and who might make some investments in Murtha's congressional district.

On Jan. 7 or 8, Murtha was taken by the "lawyer" to a Washington, D.C., house for a meeting, presumably videotaped by FBI agents.

Murtha said he agreed to try to find out whether the "Arab" could be admitted to the United States. Murtha said he also told those at the meeting he would look for investment prospects in his district because he was trying to "make sure we didn't lose that. . . ."

Murtha said the individuals at the meeting offered to put $1 million on deposit at a Johnstown bank as evidence of the Arab's purported $45 million to $50 million line of credit. He said he was also told "it's worth $50,000" to get the Arab admitted to the country and work out a business deal.

"I assumed that lawyer was going to make the $50,000," Murtha said. "Then later, I thought, "Their lawyer's getting $50,000 and he's not worth too much because [he] doesn't even know how to get his client into the country.'" Murtha said he told the FBI agents who came to his house Saturday that he was "glad as hell you have those videotapes."

Jenrette is alleged to have accepted $50,000, passed through an associate, for an immigration bill. One source claimed that Jenrett is heard on a tape to say that he had larceny in his heart and that he would take every dollar he could get his hands on.

Jenrette gave a different version in a prepared statement he issued here yesterday.

He said that "in an effort to assist someone in obtaining financing for a significant project in my district which would have provided 500 jobs, I accompanied this person to a couple of meetings with people I now understand to be FBI undercover agents."

The South Carolina Democrat said his purpose in attending the meetings was to assist in getting the project for his district. "At no time," he declared, "did I engage in any improper or illegal activities."

Jenrette said his attorney has advised him to say nothing further "in view of the fact that the FBI has apparently released a great deal of this information about the undercover operation to the press before apprising me or anyone else."

"FBI chief [William] Webster is quoted as saying he wants a full airing of the matter before the election," Jenrett continued. "I share his desire. Once the full information regarding this project is released to the public, I am confident it will establish that I have done nothing improper."

Jenrette was at his Washington home yesterday, but an aide said he would not come to the phone. An aide said he didn't know why Jenrette did not deal in his statement with the allegation that the congressman had received $50,000 as a down payment to introduce a bill keeping one of the "skeiks" in the United States.

Jenrette's wife told a television reporter, "Maybe they [the FBI] gave him so much to drink that he said 'oh yeah' to everything they asked. But he didn't come home with the $50,000."

Kelly said in a statement last night that he had been in touch with the Justice Department and "am confident I have not been involved in any criminal activity." He declined to comment further.

Sources said Kelly is shown on videotape stuffing cash from the FBI operation into his trousers and jacket pockets.

The sources said they are confident the tapes will withstand court challenges. Williams is shown on one tape talking actively, without urging from the undercover agents, about a titanium mine stock deal, the sources said.

When the FBI agents discuss giving the senator stock -- phony stock -- in the mine, he allegedly says somethging like "don't put my name on it" and the stock certificates are made out instead to a William associate, the sources said.

George Koelzer, Williams' attorney, declined to comment on the charges yesterday.

Thompson, who has denied reports he agreed to trade favors for cash, was described last night by one source as the House member who struggled with an associate over a briefcase containing $50,000.

Defense attorneys seem sure to try to use entrapment as a defense in any cases that result in indictments and go to trial. But that defense worked only once in all the trials from a famous "string" case in Washington a few years ago.

In that case, an assistant U.S. attorney, Donald Robinson, was acquitted after his lawyers showed that the undercover agents had called him repeatedly, trying to get him to come down to the undercover operation.

Sources said that in the current congressional "string" case, middlemen and associates of the members -- not the undercover agents -- brought the congressmen to the "string."

The FBI shut down the undercover operation and conducted hurried interviews Saturday when word of the "string" began to leak out to several news organizations.

The FBI Director Webster personally called off the investigation, partly because, as one source put it, "somebody let the cat out of the bag some time ago," but primarily because he felt there was no point in stringing it out any more simply to catch someone else in the web.

"Hell, that was the end of it," this source said. "He called it off to the extent of saying, 'I don't see anything else.' There's always going to be be someone who says, 'Give me another week or give me another month,' but how long do you go There may be some people who think that you wait long enough, you'll get everyone, but to say that everyone has his price is just too pessimistic."

The "string" operation began as a general property crimes investigation with an informer who had helped in the recovery of some valuable paintings that had been missing for years. After being asked what else he knew that might be of interest, the individual offered information that led to Operation ABSCAM, for Arab scam. The FBI, it was understood, decided to make "wealthy Arabs" as the lure because that lent plausibility to the approaches that were made.

The FBI agents assigned to the operation were made to look "as authentic as possible," reportedly to the extent of wearing traditional Middle Eastern garb.

Sources said the FBI had been afraid for months that the inquiry would leak out into the press at any moment. As long ago as last fall, it was said, Women's Wear Daily asked about "one name" involved in the investigation and then a local New Jersey paper called about another, but nothing ever came of their queries. The bureau decided to go ahead and "tie up the loose ends." Newsday and NBC began asking more detailed questions a few days ago.

Pretrial pubicity could be a problem, at least in the immediate future. Sources said it may take quite some time before the cases can actually go to trial.

Even so, "it's really amazing that it was kept out of the press this long," one source said.