CHICAGO (AP) - Federal authorities have seized a videotape believed to be at the center of an alleged blackmail attempt against New York Yankees slugger Gary Sheffield and his wife, a prosecutor said.

FBI agents found the tape during a search of suspect Derrick Mosley's home, Assistant U.S. Attorney Virginia Kendall said Tuesday during Mosley's bond hearing. The government said last week that it didn't know whether the videotape actually existed.

Mosley was arrested last week after allegedly asking Sheffield's business agent for $20,000 to destroy the tape that he claimed showed Sheffield's wife, gospel singer DeLeon Richards, having sex with a professional musician several years ago before her marriage.

U.S. Magistrate Judge Morton Denlow on Tuesday ordered Mosley held in jail, saying that while Mosley was not likely to be a flight risk he was concerned Mosley would try to defraud others while awaiting trial.

Defense attorney Luis Galvan said Mosley, 38, voluntarily offered to turn the tape over to prosecutors after he was arrested but the government chose to seize it with a search warrant.

Mosley has claimed that he contacted Sheffield's Chicago-based business agent, Rufus Williams, because he wanted to provide moral counseling to Richards.

Williams contacted the FBI after Mosley first contacted him on Nov. 3. Authorities said he later secretly taped a phone conversation with Mosley in which he expressed hope that the tape would be destroyed and offered to pay Mosley $1,000 for his efforts. Mosley is heard on tape saying: "I think we just gotta go a little higher … more like perhaps $20,000."