Jason Farmer, 34, was arrested over the weekend for the murder of Angela Montante at America's Inn and Suites.
Police said he checked into the motel with Montante Thursday and then killed her.
New details in court Monday morning revealed that Farmer and Montante were having sex in the room when he started choking her.
He stopped when she started panicking, but she stopped moving, prosecutors said.
Prosecutors said Farmer waited for 24 to 36 hours before calling the police.
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Authorities found him inside the motel room with the Montante's body wrapped in a blanket.
Police said he surrendered Friday night.
Investigators have not said how Montante died.
Farmer has been arrested several times over the past few years.
He is being held without bond because of two previous felonies.
Farmer is also a registered sex offender.