As Luigi Mangione returns to court in a bid to exclude evidence from his state murder trial, new details have been revealed about the 27-year-old's time in police custody and the 911 call that led to his arrest days after the fatal shooting of a healthcare executive.

During the first day of evidentiary hearings on Dec. 1, a Pennsylvania corrections officer said he closely monitored Mangione to avoid an "Epstein-style situation," referring to the suicide of disgraced financier Jeffrey Epstein while he was awaiting trial on sex trafficking charges.

"I had to fill out a form about his movements seven times an hour," said Tomas Rivers, an officer at SCI Huntingdon in Pennsylvania. Before he was extradited to New York, Mangione had meandering conversations with the guard about everything from nationalized health care and his travels abroad to the public's perception of his case, Rivers said.

The day in court also marked the first time audio was played of the fateful 911 call that led to Mangione's arrest at a McDonald's in Altoona, Pennsylvania.

The call, which ended a five-day day manhunt for the alleged killer of UnitedHealthcare CEO Brian Thompson, begins with a restaurant manager telling the dispatcher that she tried to call the non-emergency number but the call didn't go through.