Joseph James Pappas, 62, is charged with the murder of Dr. Mark Hausknecht, a prominent cardiologist, Houston Police Chief Art Acevedo announced at a Wednesday news conference, where he revealed that an arrest warrant had been issued for Pappas.
It took seconds for renowned cardiologist Mark Hausknecht, who counted a former president among his patients, to be gunned down as he cycled to work clad in his scrubs last month in Houston. "The doctor immediately went down", Houston Police Executive Assistant Chief Troy Finner told the Associated Press at the time.
In 2000, Hausknecht treated Bush for an irregular heartbeat after the ex-president complained about lightheadedness.
Houston Methodist Hospital, where Dr Hausknecht worked for almost 30 years, said in a statement it is "still in shock about the senseless killing of one of our longtime physicians". Any such substantiated threats are reported to law enforcement, she said.
The day before the shooting, Pappas, who also worked as a real estate agent, transferred the deed to his southwest Houston home to a woman who lives in Ohio.
Police were able to identify Pappas, "thanks to the fact that we have a community that's cooperative, that is a partner, that understands that they have a responsibility to play a huge role in keeping our neighborhoods safe", the chief said.
"I'm stunned", said Kathy Bilinosky, whose father was good friends with the elder Pappas.
He also said there were indications that Pappas might have worked as a constable many years ago and was familiar with the handling of firearms.
Image Houston Police released this CCTV image of the shooting suspect
Pappas' parents had lived there, Francis said, and when the mother died in 1997, he didn't notice any change in the son's behavior.
"I can tell, it is an older Schwinn", he said.
Neighbour Jim Herd said the death of Pappas' mother "hit him hard".
Herd and Bilinosky said they didn't know what Pappas now did for a living.
Little is known of Pappas' background. The company's address is in Houston.
The ads on Craigslist.com, Armslist.com and this week's Houston Greensheet include listings on July 22 for two bullet-proof vests, and listings last week for a $4,500 semi-automatic rifle, a pistol and a bullet-proof panel for a Crown Victoria.
Bilinosky said as the search continues for Pappas, she hopes that nobody else is hurt.
Police went to his home three-bedroom home in Houston on Tuesday night but he was not there. He talked to you.
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