An immigration administrative judge denied bond yesterday to a Woodbridge pizza parlor owner who has been charged in Italy in the slaying of a Sicilian judge.

In an Immigration and Naturalization Service hearing in Arlington, Judge Joan V. Arrowsmith ruled that Salvatore Inzerillo, 30, an Italian citizen and owner of Joe's Place on Rte. 1, should be held without bond because he was a risk to flee and presented a threat to the community.

Inzerillo, charged by Italian police with complicity in the death of Judge Gaetano Costa, was arrested by FBI and INS agents Tuesday at his Lake Ridge home. Inzerillo faces deportation as an illegal alien; a hearing has been scheduled March 8.

INS lawyer Robert K. Bingham argued that Inzerillo had been charged in connection with "gunning down a judge in a Free World country. He is a fugitive from justice. He has already been in hiding."

FBI agent James Glass testified that Judge Costa was assassinated in August 1980 after he began investigating narcotics trafficking in Palermo. Costa was shot three times with a .38-caliber pistol, according to the Interpol warrant.

Defense attorney Stanton Braverman said his client was no threat to society and had no criminal charges pending against him in the United States. The INS, he said, is trying to use a "back door" to return Inzerillo to Italy. Authorities there did not have enough evidence to have Inzerillo extradited, so they were trying to have him deported instead, he said.

INS documents made available state that Inzerillo is a "ranking member" of the "Inzerillo-Spatola-Gambino" mafia organization in Sicily, which also is associated with a mafia group operating in the United States.

About 18 months ago Inzerillo came to Woodbridge and became part owner of the pizza restaurant, INS officials said. Glass testified that the FBI became interested in Inzerillo after investigating an alleged drug distribution network in which cocaine was sold out of pizza restaurants in Northern Virginia and Washington.

Wiretaps and interviews with those allegedly involved in the drug operation produced Inzerillo's name.