HOUSTON (CBSDFW.COM/CBSNEWS.COM) – In a chilling interview, a former friend of Joseph Pappas told the CBS Houston affiliate that he believes the suspected killer of a Houston cardiologist has a hit list and may be hunting his next victim.

“I personally do not think the doctor is the only person that he is going to target,” the friend told KHOU on the condition of anonymity. “I think [Dr. Mark Hausknecht] was number one on the list. And Joe is extremely intelligent. He’s patient, he’s unassuming, he’s a deadly shooter.”

Dr. Mark Hausknecht with President George H.W. Bush. (CBS News)

Pappas is still on the run and is armed and extremely dangerous, according to Houston Police Chief Art Acevedo.

The former friend says Pappas is highly-skilled and has a stash of firearms. He’s an expert marksman who regularly competed in shooting competitions. He’s also a former law enforcement officer who worked as a deputy constable in Precincts 2 and 7.

Hausknecht treated George H.W. Bush in February 2000 for an irregular heartbeat after the former president complained about lightheadedness while in Florida.

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