EAST BOSTON – An East Boston District Court judge ordered a Revere man held without bail Monday after he allegedly stabbed and killed a 50-year-old man in the basement of a Chelsea Street apartment building, according to a press release from Suffolk District attorney spokesman Jake Wark.Boston Police charged Cristian Santa, 20, of 72 Shirley Ave. #1, with one count of murder Saturday, according to Boston Police.Investigators believe Santa killed John Barrientos in the older man’s 220 Chelsea St. basement apartment sometime around 5 a.m. Friday, and then dragged him outside to an alley, where he was found about an hour later, Wark said.”Following an investigation which included forensic examination of the crime scene and interviews of witnesses and the suspect, Mr. Santa has been positively identified as the person responsible for the death of Barrientos,” Boston Police Officer Paul McLaughlin said in a police report.At Santa’s bail hearing, Assistant District Attorney Ursula Knight told Judge Roberto Ronquillo Jr., that Boston Police were dispatched to the alleyway Friday morning for a report of a heart attack, Wark said in the release.”When they arrived, they found a bloody scene that instead suggested foul play – a determination backed up by an autopsy this weekend that revealed multiple stab wounds and fatal blunt force trauma,” he said.According to the police report, Boston Police found Barrientos “laying motionless on his back with multiple stab wounds to his chest area and blunt trauma to his head.”Evidence at the scene, including two bloody fingerprints later found to match Santa’s, led detectives to the boiler room of the apartment building, where investigators believe Barrientos was slain, Wark said. Santa allegedly attempted to remove the body from the basement by dragging it upstairs, but then abandoned that effort.Wark said Santa’s motive remains under investigation, but police believe he and Barrientos were drinking together Thursday night into Friday morning.”Witnesses told authorities that they later heard screams and ‘thudding’ sounds at about 5 a.m.,” Wark said in the release. “At about 6 a.m., Santa made his way home to his residence in Revere.””Veteran investigators said this was among the grisliest crime scenes they’d ever encountered,” District Attorney Daniel Conley said in a statement.Santa is represented by attorney L. Manuel Macias of Boston, Wark said. He will return to court on July 27.Taylor Provost can be reached at [email protected].