District Attorney Richard A. Brown says Jason Bohn surrendered Friday night in White Plains.
He was awaiting arraignment Saturday in Queens on murder, evidence tampering and other charges.
Police found Danielle Thomas dead Tuesday in the pair's Astoria apartment. Her body was in the bathtub, surrounded by bags of ice.
On June 7, Thomas reported that she'd been assaulted.
The prosecutor says that while Thomas was at the police station, Bohn allegedly called her cell phone and threatened to "hunt her down" and "bash in her skull." Brown says the call was on speaker and a police sergeant heard it. She received an order of protection.
Bohn's attorney did not immediately return a call for comment.
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