2 witnesses in MU professor's homicide speak up after killer's suicide COLUMBIA, Mo., Jan. 30 (UPI) -- Police said tips from two witnesses led to identifying a man who committed suicide in August as the killer of a University of Missouri professor in 2005. University Police Chief Javk Watring said Wednesday in Columbia that Timothy Hoag, 35, who killed himself Aug. 9 by jumping off a parking garage, killed Jeong Im, 72, on Jan. 7, 2005, the Columbia Daily Tribune reported. Watring said the motive for the fatal stabbing probably never will be known. Police said in the 2005 incident, the microbiologist's body was found in the trunk of his car, which had been set on fire. At least two witnesses who thought Hoag was the killer were too afraid to come forward with information while Hoag was alive. They described Hoag as violent, the Tribune reported. Police received a tip Dec. 21 from one witness that Hoag may have been the person who killed Im. After investigators learned Hoag had killed himself, they got a sample of Hoag's blood, which the Missouri State Highway Patrol Crime Lab matched to the blood, hair and DNA collected at the 2005 crime scene, MU Police Capt. Brian Weimer said. Another witness came forward to give other information that implicated Hoag. The newspaper reported police department described a person of interest in the case and are looking for the owner or driver of a faded red 1980s model Ford F-150 pickup seen near the scene of the crime.