Houston cops on Wednesday identified the suspect who allegedly shot and killed ex-President George H.W. Bush's cardiologist - and said he may have been motivated by his own mother's death 20 years ago during an operation performed by the victim.
One tip seems to support the police department's theory that Hausknecht was targeted: Pappas's mother was once Hausknecht's patient and died during surgery more than 20 years ago.
The family of a cardiologist who was gunned down while riding his bike to work last month has issued a statement about his suspected killer.
"This man is unsafe, this man is capable, this man has some skills", Houston Police Chief Art Acevedo said at news conference, according to The Houston Chronicle, noting he likely had multiple firearms and had not been seen for almost two days.
Hausknecht treated Bush in February 2000 for an irregular heartbeat after the ex-president complained about lightheadedness while visiting Florida.
As authorities try to locate Pappas, they are once again requesting help from the public.
The suspect is considered armed and risky, and reportedly made phone calls in which he discussed committing suicide.
"This man is unsafe, this man is capable, this man has some skills (with firearms)", he said.
Bilinosky, who grew up on the street behind the Pappas home in southwest Houston, said the younger Pappas was respectful but she didn't spend much time with him or his sister. He was wearing a white hat, navy blue polo shirt, white shorts and a backpack. He died in hospital.
The chief said Pappas is very fit, and that he's likely getting around on his 10-speed bicycle, which he rides "extensively and nearly exclusively".
Houston police have described the area where Hausknecht was killed as relatively safe.
Finally, after passing him by, the murderer turned on his bicycle and fired several shots in Hausknecht's direction. Hausknecht, a cardiologist, was reportedly riding near the Texas Children's Hospital when he crossed paths with the gunman on a bike.
Police were perplexed by the killing and described it as a "real whodunnit".
Following Hausknecht's death, the former president released a statement expressing deep sadness. "I will always be grateful for his exceptional, compassionate care".
The doctor's widow has since spoken out to call for stricter gun laws.
This undated photo provided by the Houston Police Department shows Joseph James Pappas.
Herd and Bilinosky said they didn't know what Pappas now did for a living.
He does not appear to be married and he has one sister.
Police went to Pappas' three-bedroom home in Houston, Texas, on Tuesday night but he was not there.