Attorney General Janet Reno came under heavy Republican fire yesterday for the sudden discovery of new evidence about the final fiery day that ended the 1993 Branch Davidian siege, but Democrats asked why no one was demanding the resignation of FBI Director Louis J. Freeh.

Reversing itself after six years of denials, the FBI acknowledged Aug. 25 that its agents fired "a very limited number" of potentially incendiary tear gas cartridges on the last morning of the 51-day siege near Waco, Tex. Reno, who had been repeatedly assured no such weapons had been used, has announced that she will appoint an independent investigator to determine whether the FBI tried to cover up its use of the devices.

Two Republican presidential candidates, Sen. Orrin G. Hatch (R-Utah) and businessman Steve Forbes, said they would have fired Reno if they had been in the White House.

"The Waco thing is simply the latest of a long string of very serious political abuses," Forbes said on NBC's "Meet the Press." Speaking on the same program, Hatch said he would not have chosen Reno to begin with but in any case "would have fired [her] by now."

Hatch said there were several memos, one of them prepared by the FBI and made available to the Justice Department around 1996, that stated that "military canisters" were used on the last day of the siege, which left about 75 people dead. Hatch said "anybody with brains" would have realized "that that meant those were explosive canisters."

Asked about Hatch's assertions, Justice Department spokesman Myron Marlin said, "These are allegations that will have to be looked at, and that is why the attorney general has said she is looking for an outside investigator."

Rep. John Conyers Jr. (D-Mich.) scolded Hatch for blaming Reno for what the FBI belatedly discovered in its files: two videotapes that also recorded ground radio traffic among FBI agents and that confirmed the use of potentially flammable tear gas cartridges in an early morning effort to penetrate an underground storm shelter.

"Janet Reno is now being blamed for what the FBI didn't do," Conyers protested on "Meet the Press." Withholding of evidence by the FBI deserves to be independently investigated, Conyers said, but he predicted that any new inquiry would still conclude that it was the Branch Davidians who started the fatal fires hours after the tear gas usage.

Sen. Charles E. Schumer (D-N.Y.) said on ABC's "This Week" that "sort of a double standard" was at work in demands that Reno resign while Freeh should not. What was important now, he said, was to find out whether only the information about the tear gas was withheld and how far up the chain of command that information got.

Sen. Phil Gramm (R-Tex.) said he still faulted Reno because the Waco discovery was just one of "a long series of cases where the attorney general seems to be always the last person to know."

"I'm not questioning her intentions," Gramm said on ABC, "but I think she's given good intentions a bad name."

A filmmaker who has challenged the conclusion that the Branch Davidians set the fires, Michael McNulty, said on "Fox News Sunday" that he has come up with film that "clearly shows" a gunfight between cult members and federal operatives at the back of the only exit of the Branch Davidian building that had been unmolested by tanks. He said this left the women and children inside the building with "no way out."

"They had a choice of being shot to death or burning to death," McNulty said. He said 17 people were found "shot to death in that immediate vicinity." How many died by their own hand and "how many died by the hands of the government is an issue that needs to be clarified," McNulty said.

Former FBI agent Richard Schwein, who was in charge of one of the shifts at Waco, said charges of government gunfire being directed at the one open exit were "absolutely false."

"No FBI agent fired any rounds from their weapons at Waco," Schwein said on "Fox News Sunday." He added that "there were no Delta Forces or special operations soldiers in an operational capacity at Waco" either. He said the Army had what he recalled as "three observers" there "but they took absolutely no part in the operation," which would have been a violation of federal law.

"Everyone on our side, and the FBI's side, were in armored vehicles, so I don't know how you'd have films of anybody firing into the back of the building," Schwein said. "No one was on foot because we had no body armor that would stop the rounds they were firing."

CAPTION: "The Waco thing is simply the latest of a long string of very serious political abuses," said Steve Forbes, a Republican presidential contender.

CAPTION: Attorney General Janet Reno has said she will appoint an independent investigator to determine whether the FBI tried to cover up its actions.