A mixed martial arts fighter was one of two Americans gunned down in an execution-style killing near the San Ysidro border crossing Monday morning.
Mexican authorities say Sergio Salcido Luna and Kevin Joel Romero were waiting in their company truck while waiting to cross into the U.S. before dawn.
A gunman walked up to the white Mazda truck with California license plates and opened fire at least five times, killing both men as they sat in traffic.
Investigators are still trying to determine a motive for the killing. Salcido, 25, was a professional fighter who began his career in MMA in Bakersfield.
He also worked for a San Diego company called West Coast Beverage Maintenance, which is located on Morena Boulevard.
Salcido, and fellow worker Kevin Joel Romero, 28, of San Diego, were carpooling into work in company truck from their homes in Tijuana, when they were shot and killed.
The owner of West Coast Beverage didn't want to be identified by name, but he told NBCSanDiego the men were very close friends.
He says Salcido and Romero worked for West Coast for a little more than a year, and they were hard workers who were "very respectful" and "would walk into a room and give you a handshake and a hug."
The owner says Romero was married and had adopted his wife's 5-year-old son.
He also says the men lived clean lives. Romero didn't drink and they both trained together as Salcido prepared for upcoming fights.
The owner of West Coast beverage said Romero grew up in San Diego, but he moved to Tijuana because it was cheaper to live there.
He also says both men always wanted to work extra hours to make more money, and they never got into trouble.
Romero and Salcido were shot in the head, arms and body. Investigators told the Associated Press they found 9mm shell casings at the scene. That ammunition is used in weapons favored by drug cartel gunmen in Mexico.
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