Cardiologist Dr. Mark Hausknecht was shot and killed while riding his bicycle to work in the mid-morning hours on Friday.
A woman who works close to the spot where he was gunned down says she's concerned that the shooting happened in what is typically one of the safest parts of town.
"Just unbelievable that something like that could happen that close to home and to a physician, too, that saves lives," Shannon Carter said.
Police have released a sketch of the suspect who is described as a white or Hispanic man in his 30s wearing a dark jacket. Police said the suspect had a tan baseball cap, sunglasses and was clean shaven.
"I talk to a lot of people every day and they all ask about this guy, what happened, you know? I don't know what happened, but I am just trying to help," said James Pierce who has been standing outside in the Medical Center, holding a sign to help find the man accused of killing Dr. Hausknecht.
Over the weekend, the Houston Police Department released surveillance photos near the scene where Dr. Hausknecht was killed.
The pictures show Dr. Hausknecht in green and the shooting suspect in red. The doctor can be seen heading north at 6700 Main and crossing into the West Holcombe Boulevard intersection.
RELATED: Dr. Mark Hausknecht identified as Houston cardiologist shot to death by gunman on bike
Other photos show the suspect behind the doctor. The shooting happened moments later, one block away.
Hausknecht was a private doctor who worked at Methodist Hospital and Memorial Hermann Hospital.
On Sunday, friends of Hausknecht remembered the prominent doctor.
"He just played a very great role in the community," one woman said.
Hausknecht's wife, Dr. Georgia R. Hsieh, called his death "senseless."
"So many have asked what can be done to help. While law enforcement has given you their focus on finding the criminal, I am asking you to use your vote and your voice to stem the tide of this growing public health epidemic," she said in the statement.
READ MORE: Full statement from Dr. Georgia R. Hsieh
As the search continues for his killer, parking manager Gary Hollie is telling his employees to be on the lookout for the suspect and to stay safe.
"We are a little more cautious, making sure we watch a little close, just making sure we are being careful," Hollie said.
UPDATE#3: Road traveled: These still photos show Dr. Hausknecht (in green) & the suspect (in red). The Dr. is headed north at 6700 Main & crossing into the W Holcombe Blvd intersect. 2nd & 3rd photos are suspect behind the Dr. The shooting happened moments later, one block away. pic.twitter.com/d56PDIu4Ah— Houston Police (@houstonpolice) July 23, 2018
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