Authorities in Texas have released a composite sketch of the suspected gunman responsible for killing a cardiologist who had previously attended to former President George H.W. Bush.

As the Dallas Morning News reported, 65-year-old Mark Hausknecht was fatally shot as he rode his bicycle on the property of Houston’s Texas Medical Center on Friday morning.

Houston Assistant Police Chief Troy Finner said the victim “immediately went down” after he was struck at around 9 a.m.

Hausknecht was transported to Herman Memorial Hospital, where he was pronounced dead.

Witness descriptions led investigators to issue an alert for a clean-shaven man in his 30s.

The suspect was described as white or Hispanic and standing at about 5 foot 10 inches tall with a slender build. He was last seen wearing a gray jacket, khaki shorts, a tan baseball cap and sunglasses.

Houston Police Chief Art Acevedo described the deadly shooting as a “crime that doesn’t make sense.”

Initial reports indicated authorities had not determined a motive for the attack.

Investigators were also in the process of searching for surveillance footage positioned nearby that might have captured the crime or other evidence.

The 41st president issued a statement honoring the kindness and professionalism of his doctor, as reported by CNN.

“Mark was a fantastic cardiologist and a good man,” Bush said. “I will always be grateful for his exceptional, compassionate care. His family is in our prayers.”

The 94-year-old former president’s statement also sent “his most sincere condolences to the Hausknecht family, his colleagues at Houston Methodist, and his friends.”

[Featured image: Houston Police Department]