PORTLAND, TEXAS (ABC News) -- Mary Kristene Chapa is intent on helping police catch the man who shot her in the head and murdered her girlfriend at a Texas park last month, even from her hospital bed as she recuperates from brain injuries.
"She wants very badly to help us identify Mollie's murderer," Portland, Texas, Police Department Chief Randy Wright said.
Police released a second sketch of the suspect today, which was refined from the first version Chapa worked with a forensic artist to create.
"It is unusual to go back and refine a suspect drawing," Wright said. "But in this case, our eyewitness sustained a brain injury that initially affected her ability to communicate effectively. The good news is she has made exceptional progress. Her sight and speech have improved and she can now interact with the artist much better."
Wright said Chapa had requested a second meeting with the sketch artist to refine the image.
The physical description of the suspect did not change from the first version Chapa provided, Wright said.
The assailant is described as a white male in his 20s, 5 foot 8 inches tall, thin build, 140 pounds, with brown hair and a scruffy beard.
Chapa and her girlfriend, Mollie Olgin, were both shot in the head at Violet Andrews Park in Portland on June 22.
Olgin was found dead next to her girlfriend by a couple the next morning. Police believe the women were shot sometime around midnight.
The shooting is not being investigated as a hate crime.
A close friend of Olgin remembered the last time she saw her "bubbly" friend and how happy she was. She said Olgin proudly showed off a ring that said "Mollie Loves Mary," which is Chapa's first name, though she goes by her middle name, Kristene.
"If you were her friend or [she] barely met you, she'd give you the world and then some," said the friend, who did not want to be identified.
The Portland Police Department is being assisted by federal law enforcement agencies, the Texas Rangers and Texas Department of Public Safety.
Several vehicles were at Violet Andrews Park the night of the shooting, according to witnesses. Officers are appealing to anyone who was in the area that night to come forward with any information they may have, no matter how inconsequential it may be seem.
Mario Olgin, Mollie's father, told ABC News' Corpus Christi affiliate that he is hopeful the person who did this to his daughter would be apprehended.
"She was happy," Mario Olgin said. "Justice will be served."
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