HOUSTON -- Police are searching for a man now charged with murdering a prominent Houston doctor.
Dr. Mark Hausknecht was gunned down as he rode his bicycle to work in the Texas Medical Center on Friday, July 20.
Houston police say tips that came in on Tuesday afternoon led them to Joseph James Pappas. Houston Police Chief Art Acevedo says Pappas' mother died during surgery more than 20 years ago, and they believe that is the motive in the murder of Dr. Hausknecht.
At 4 a.m. Wednesday, police performed a search warrant. Pappas, 65, was not in the home at the time of the police search and cannot be located. A warrant has been issued for his arrest.
Anyone with information on Pappas' whereabouts is asked to call 911. He is considered armed and dangerous, and police believe he may be suicidal.
On Monday, Houston police tweeted out video of the suspect in a nearby neighborhood immediately following the doctor's shooting.
SEE ALSO: Mark Hausknecht seen in new surveillance photos with suspect who shot and killed him
Anyone with information is urged to contact the Houston Police Department Homicide Unit at 713-308-3600, or Crime Stoppers at 713-222-TIPS.