Loved ones of Houston cardiologist hope new video will lead to his killer

Loved ones of a prominent Houston cardiologist who was shot and killed while riding his bike to work hope new surveillance video will lead to his killer.

"Here is a man who took an oath to save and preserve life, who was gunned down for whatever reason," says Dr. Sally Miller.

The reason for Dr. Mark Hausknecht's slaying and the person behind it continues to elude police.

Many days have passed since Dr. Hausknecht's murder. It was just before 9 a.m. on July 20 when the cardiologist was northbound on Main past Holcombe. Two blocks later, a man riding a bike shot Dr. Hausknecht. After firing three shots, the killer continued on Main Street then rode west on Southgate.

Dr. Miller knew the doctor both personally and professionally.

"Because I had worked in my husband's office, he is a physician, and Dr. Hausknecht was a referral for cardiology."

Dr. Hausknecht was admired by his peers and patients at the DeBakey Heart and Vascular Center at Houston Methodist.

Dr. Miller took it upon herself to post flyers about Dr. Hausknecht's killer.

Many folks are still puzzled over why someone would take the life of a successful cardiologist.

We asked Dr. Miller, who has known Dr. Hausknecht for 30 years, if she thought the shooting was random or targeted.

"It looks like it wasn't an accident," Miller said.