A suspect identified as Juan Mario Trejo has been arrested in connection with a shooting on a Foothill Transit bus in Baldwin Park.

BALDWIN PARK, Calif. (KABC) — A 32-year-old West Covina man was arrested Tuesday in connection with a shooting on a Foothill Transit bus in Baldwin Park.

According to the California Highway Patrol, Juan Mario Trejo was arrested just 20 hours after the shooting that left an innocent passenger injured. Trejo was arrested in East Los Angeles and charged with attempted murder.

He is being held at the Los Angeles County Sheriff's Department Inmate Reception Center on $1 million bail.

“During the course of the investigation, several crucial leads were developed that led to the arrest of the suspect,” CHP Lt. Saul Gomez said during a news conference Tuesday.

Gomez said footage from inside the bus played “a very important role” in locating Trejo.

“This individual has had several run-ins with law enforcement. That's all I can tell you,” Gomez told reporters.

Filming details

Investigators said gunfire erupted around 6 p.m. Monday as the bus stopped at the Puente Avenue stop on the westbound 10 Freeway.

Trejo and another man began arguing, leading Trejo to pull out a gun and open fire, according to the CHP. Authorities said the bus driver tried to calm the situation before the suspect pulled out his gun.

“The bus driver, from what we understand, did everything he was trained to do in trying to deescalate the situation and mitigate it as best he could,” Gomez said Monday. “Unfortunately, we have someone who was injured as a result of this crime.”

A woman in her 50s was inadvertently struck and then rushed to the hospital with injuries described as non-life-threatening, the CHP said. She has since been released and is expected to make a full recovery.

The second person involved in the fight was not injured.

Meanwhile, Doran Barnes, CEO of Foothill Transit, thanked CHP officers for their quick work.

“Our communities face many issues, including mental health, homelessness and substance abuse,” Barnes said. “And unfortunately, we see these issues largely impacting our community and spilling over into our transit system. Safety continues to be our top priority and we will continue to do everything we can to keep the system as absolutely safe as possible .

The incident remains under investigation. Anyone with additional information is asked to call the CHP South Division Major Crimes Unit at 323-644-9550.