Just two weeks before he watched an armored car robbery and murder right in front of him, James Contacessa saw something odd -- his acquaintance Christian Tarantino walking into his office building, where the crime later took place, he testified Monday.

A couple of hours after the 1994 robbery, which took the life of armored car guard Julius Baumgardt, Contacessa said that Nassau police showed him photos of several people, including Tarantino, now on trial on murder charges in federal court.

During questioning by federal prosecutor Sean Flynn, Contacessa said he told police that he knew Tarantino and didn't see him at the robbery -- but didn't mention he'd seen Tarantino at the crime scene earlier. Prosecutors said Tarantino wore a pig's mask during the robbery.

Tarantino, a Dix Hills gym operator, is charged with killing Baumgardt and two associates he feared would turn him into the authorities. They are Louis Dorval, who also took part in the Muttontown robbery, and Vincent Gargiulo, who prosecutors say sent police a tape recording of Tarantino implicating himself in the crimes.

Contacessa's refusal to tell all he knew about Tarantino's involvement in the robbery has gotten him into trouble, he testified. He pleaded guilty last week to lying to a federal agent about this case, and faces up to 5 years in prison. He said he hopes his testimony earns him a lighter sentence.

He also acknowledged he'd pleaded guilty in 1997 for paying someone to take his investment banking license exam for him, after he'd failed it once.

Contacessa said he'd known Tarantino and his brother Steven for a few years from working as a party promoter at various Nassau bars. He said their relationship was "cordial."

"I got kind of nervous" when police showed him Tarantino's photo right after the slaying, Contacessa said. "If he had participated, then he saw me --"

Tarantino's attorney, James Froccaro, interrupted him with an objection and attorneys met at the bench. When testimony resumed, Contacessa said he saw Tarantino a few years later at the Feast of San Gennaro in Little Italy. He said he took Tarantino aside and told him police had shown him his picture.

"I wanted him to know that I never said anything about seeing him there in the weeks prior," he said. "He just looked at me and walked away. . . . I guess I was just looking for reassurance. I wanted it to be good."

After a similar encounter in 2003 with Tarantino's brother Steven ended with Contacessa getting punched in the head, he said he got a call from a mutual acquaintance who advised him that "I should keep my mouth shut about the photos."

Judge Joanna Seybert allowed Froccaro time to prepare for cross-examining Contacessa. The trial resumes next week.

Earlier Monday, jurors also heard a tape recording that prosecutors say was made by Gargiulo in which they say Tarantino discusses the robbery and dumping Dorval's body in the Atlantic Ocean.

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