The Associated Press reported that an arrest warrant has been issued for the killer of a Texas cardiologist who use to take care of former President George H.W. Bush.

Art Acevado, Chief of the Houston Police Department that the suspect is Joseph James Pappas, 65. Despite his age, Acevado said he should be considered armed and dangrous.

Dr. Mark Hausknecht was the cardiologist that was murdered by Pappas. Hausknecht operated on Pappas' mother over twenty years, and she died on the operating table during the procedure. Hausknecht was shot to death by Pappas while riding his bike on July 20th to work at Texas Medical Center.

Authorities said Pappas rode past Hausknecht on his bike, turned around on his bicycle, and fired at the doctor. A sketch drawn of Pappas', showed him last seen wearing glasses and a cap. Authorities released surveillance pictures of the incident, and you are clearly able to see the two bicyclists riding by one another. Authorities had previous reports that they suspected Hausknecht had been targeted. Hausknecht treated bush back in the year of 2000, when the former president was dealing with an irregular heartbeat.