A D.C. Superior Court judge yesterday doubled the bond of a man charged in the slaying of exiled Iranian diplomat Ali Akbar Tabatabai, after concluding that his release two weeks ago was improperly financed by an employe of the Iranian government here.

Judge Fred B. Ugast doubled the bond from $50,000 to $100,000 for Ahmed Rauf, also known as Horace A. Butler, and said he will review the source of any funds used to assist Rauf in attempting to make that bond.

Rauf was indicted with three others on Thursday after a federal grand jury concluded a year-long investigation of the execution-style murder of Tabatabai last July in Bethesda. The indictment labeled the killing a conspiracy in which cash payments were involved, but there was no indication as to who ordered the killing or paid for it.

The indictment charged Daoud Salahuddin, 30, also known as David Belfield, who had served as a security guard for the Iranian interests section of the Algerian Embassy here, with obtaining a U.S. Postal Service vehicle, going to Tabatabai's home disguised as a postman, luring him to the door, and then shooting him. Salahuddin has fled the country and is believed to be living in Tehran.

The indictment also alleged that Rauf helped Salahuddin obtain the mail truck and later disposed of the murder weapon. The indictment charged that Ali Abdul-Mani, 26, rented the vehicle used for the escape, and that William Caffee, Jr., 34, also known as Kalid, wiped the car clean of fingerprints and abandoned it in the District. Abdul-Mani turned himself into the FBI yesterday.

Rauf, who had been in custody since last July, had been released on $50,000 bond on July 1 after bondsman John Light was paid $5,000 cash and Rauf's mother, Effie Butler, agreed to use her house as collateral. Testimony, however, showed that the $5,000 was paid by a family friend named Scott Fontaine.

Fontaine, 32, of 609 Keefer Pl. NW, testified that he worked at the Iranian interests section at the Algerian Embassy here, and acknowledged that he had paid the money. He said it came from his savings, which he kept in a paper bag in his basement. Fontaine also said that he had gotten his job through Salahuddin, whom he had known for 10 years.

Prosecutors alleged that Fontaine also had a role in the Majlis Shura, said to be the governing body of the Islamic Center here, which circulated a fund-raising notice supporting Slahuddin's escape from the United States and raised a $2,200 defense fund for Rauf.

"The money here has come from an extraordinarily tainted source," said Principal Assistant U.S. Attorney Robert W. Ogren. "From Iran [the Iranian interests section], from people who are sympathetic with the cause of the fugitives and terrorism and the political killing charged in the indictment."

Fontaine's testimony and Ogren's statement were the first indication as to how Rauf's release had been financed.

Ugast said that because Fontaine was "part and parcel" of, and had an "active role in carrying out, the policies of the Iranian interests section and Majlis Shura," the $5,000 Fontaine supplied as payment for the bond charge "came from an inappropriate source."

"Mr. Fontaine is an individual actively involved with organizations that condone and approve" of fugitives fleeing "from our courts," Ugast said.

Rauf's attorney, Thomas Abbenante, sharply attacked the government's position and said that it should be clear Rauf would not flee because he had not made such attempts while free on the $50,000 bond.

Abdul-Mani had been charged with conspiracy to murder and to prevent the apprehension of the murderer, and with perjury in connection with his statements before a federal grand jury investigating the Tabatabai slaying.

Abdul-Mani, 26, also known as Lee Curtis Manning, last of 1650 Fuller St. NW, was charged with falsely reporting to law enforcement authorities that the getaway car had been stolen, when it allegedly had been abandoned in D.C. as part of the conspiracy.

Abdul-Mani had called the FBI's Washington Field Office on Thursday and indicated he wanted to surrender. Then, Thursday night, he called WRC-TV (Channel 4) anchorage Jim Vance and said he wanted to be interviewed by that station before surrendering. One of the station's reporters, Jack Cloherty, interviewed Abdul-Mani for about an hour yesterday.

In a part of the interview shown by WRC last night, Abdul-Mani said he had nothing to do with the murder and complained of FBI harassment. He acknowledged renting a car, but said he did not loan it to Salahuddin.

Abdul-Mani called the FBI from the television station, according to Barbara Holtzberg, WRC's spokeswoman. He surrendered at about 2:30 p.m. at the corner of California Street and Massachusetts Avenue NW, following prayers at the Islamic Mosque, according to Ron Dervish, an FBI spokesman.

Abdul-Mani was accompanied by his attorney, Melvin A. Marshall, and his wife, Habiba.

Dervish said that Habiba Abdul-Mani will receive the $1,000 reward offered by the FBI to the person who provided information leading to Abdul-Mani's arrest. According to Dervish, in his telephone call to the FBI Thursday Abdul-Mani asked whether anyone from his family could claim the reward, although that was not a prerequisite for his surrender. The FBI decided to give the money to his wife.

"It's well worth it to us," Dervish said.