HARRIS COUNTY, Texas -- A Navy veteran was killed and another man was injured after a reported argument outside of a Katy-area pub overnight.

It happened in the parking lot of EinStein's Pub on Mason near Cimarron. Investigators believe the incident started with four men involved in a verbal altercation that led to a fight. Someone pulled out a gun and opened fire.

Harris County Sheriff’s Deputies say a 30-year-old Navy veteran was killed, and a 23-year-old man was pistol-whipped He was taken to the hospital with head injuries.

The victim’s mother is hoping for some answers and justice.

“Tough, hands-on type of a guy. He never wanted to sit behind a desk,” said his mother, Robin Raab. Instead, 30-year-old Corey Raab wanted to travel the world, and just like his older brothers, he did it by joining the U.S. Navy. He heroically served two tours.

His family rushed over as soon as they heard the news.

“I can’t believe it’s real. I can’t believe my son, my youngest child, is gone forever,” said Raab.

Authorities now investigating to figure out a motive.

“Please, please come forward, and let us find who did this, and find justice,” said Raab.

Harris County deputies say one of the two men on the run was last seen wearing jeans and a white t-shirt, the other a plaid shirt and jeans. They took off in a dark SUV.

If you have any information, you’re urged to call Houston Crime Stoppers at 713-222-TIPS or the sheriff’s office at 713-221-6000.