NEW YORK CITY (TIP): A Bronx man who died after being pulled from his burning apartment in October was strangled to death, officials said Wednesday. Keith Alexander, 53, died from “asphyxia by neck compression” when he was found in a fire around 10 p.m. Oct 29, the city medical examiner determined. Paint thinners were used to ignite the blaze in his home on Weeks Ave. near the Cross-Bronx Expressway, sources said. The blaze may have been set to cover up evidence of the homicide, investigators believe. Security video captured a man and a woman entering and leaving the apartment numerous times in the hours before Alexander’s death, including five minutes before a 911 call was made, sources said. Alexander had burns from the waist down, sources said. He was taken to Bronx-Lebanon Hospital where he died, police said. Alexander had six prior arrests, including one for criminal possession of a weapon dating to 2003, police said.