The judge presiding over the racketeering trial of reputed mob boss Joseph Ligambi and six associates dismissed a juror this morning, one week after reports of a mob-related killing in South Philadelphia.

U.S. District Judge Eduardo Robreno didn't publicly explain why he dismissed the man, identified as Juror No. 5. But lawyers had previously said the man was the only juror who admitted during private talks with the judge that last week's murder of Gino DiPietro might influence his view of the case.

"Juror No. 5 will no longer be sitting with us," Robreno told the remaining 11 jurors and 5 alternates as the trial resumed. "You should not speculate as to the reasons for that. He has been dismissed from juror service."

DiPietro, 50, was gunned down outside his home on the 2800 block of Iseminger Street on Wednesday afternoon. Police later charged reputed mob soldier Anthony Nicodemo, 41, with the killing.

Investigators have offered no motives for the killing. DiPietro had a criminal record for drug dealing. But some reports said he also was rumored to have been cooperating with federal organized crime agents.

Neither Nicodemo nor DiPietro had any clear ties to the ongoing federal trial.

The shooting came on the last day of a prosecution case against Ligambi that has largely lacked any evidence of violence. Prosecutors say the 73-year-old mob boss oversaw a crime family that used its past reputation and threats to control illegal gambling, extortion and loan-sharking rackets.

The defense is expected to rest its case today, and jurors will return in January for closing arguments and deliberations.

Contact John P. Martin at 215-925-2649, at jmartin@phillynews.com, or @JPMartinInky on Twitter.