SWAMPSCOTT – A Swampscott man is being held without bail following his arrest for allegedly threatening to kill his ex-girlfriend and stalking her, according to court documents filed in Lynn District Court.Mark C. Sacco, 43, of 63 Pleasant St., allegedly hit his ex-girlfriend’s knees with a 5-pound weight, threatened to kill her and left threatening messages on her cell phone saying he would “send someone to kill her,” according to an incident report filed by Lynn Police.Judge Stacey Fortes-White ordered Sacco held without bail after the Swampscott man’s arraignment Friday in Lynn District Court.He is due back in court Tuesday for a dangerousness hearing.Sacco faces charges of stalking, assault and battery with a dangerous weapon and threat to commit a crime.Court records show Sacco’s ex-girlfriend, a 50-year-old Lynn woman, told police she had a relationship with Sacco that lasted “approximately six months.”The woman told police she had broken up with Sacco “a few weeks ago,” according to the report, but he continued asking her out and she kept refusing.The arrest report states Sacco asked the woman to come to his house in Swampscott last weekend, but after she refused, the suspect showed up at her apartment in Lynn, even though the victim kept asking him to leave.”At one point the suspect became upset because the victim refused to go to his apartment,” said the report filed by Lynn Police officer Ray Guillermo. “He grabbed a 5-pound weight from the apartment and started hitting the victim on both of her knees approximately seven times,” the officer stated in the report.The victim stated she ended up with “some bruises” on both of her knees, according to the report, and that while he was hitting her, he kept telling her, “it would get worse.”Later in the day, Sacco left the apartment, but continued to call his ex-girlfriend, according to the report. She told police she turned off her cell phone to avoid his calls and he then allegedly left two threatening messages, the report states.In a separate incident on Wednesday, the victim was driving on Highland Avenue when Sacco allegedly followed her home and drove next to her and started yelling at her out his window, according to the report.Lynn Police obtained a warrant for Sacco’s arrest after the victim reported these incidents on Wednesday. Sacco was later arrested by Swampscott police and transported back to Lynn where he was booked without incident.Matt Tempesta may be reached at [email protected].