TUCSON, Ariz. — Authorities in Arizona responded to an active shooter scene at a Tucson Amtrak station on Monday.

Here are the latest updates (in MT):

1:17 p.m.

A DEA agent was killed in Monday's shooting. Another DEA officer was seriously injured.

According to Tuscon Police Chief Chris Magnus, the regional Counter Narcotics Alliance was conducting a routine interdiction check.

Officers detained one person on the second level of the double-decker car, and another opened fire on the officers.

A TPD officer heard the shots and ran into the conflict and was shot. He was injured and is in stable condition.

The suspect who was firing at officers barricaded himself into a bathroom. That suspect died.

The injured DEA officer was evacuated from the train and taken to the back of the patrol car. He is hospitalized at Banner University Medical Center.

The other officers were taken by ambulance to Banner as well.

No passengers or bystanders were harmed.

Mayor Regina Romero released this statement:

12:48 p.m.

According to Sun Tran, downtown bus routes are not able to service the Ronstadt Transit Center. For customer service, riders should Ucall customer service for assistance planning your trip: (520) 792-9222.

12:17 p.m.

According to the Associated Press, one person is in custody and that passengers huddled as they heard gunshots.

11:13 a.m.

KGUN reporter Evan Courtney captured this image at the scene of the shooting.

10:23 a.m.

Tucson police have secured the scene. TPD will provide an update at the main station downtown later today.

10:11 a.m.

Amtrak said a shooting happened onboard Amtrak's Sunset Limited train in Tucson.

"The Sunset Limited, Train 2, was traveling from Los Angeles to New Orleans, and arrived at the Tucson station at 7:40 am local time," Amtrak spokesman Jason Abrams told KGUN9 via email. "There are 137 passengers and 11 crew members, with all passengers and crew now evacuated to the station. There are no reported injuries to the crew or passengers."

9:56 a.m.

KGUN9 has confirmed that at least one person was shot.

9:52 a.m.

Tucson police responded to an active shooter scene at a Tucson Amtrak station at 500 N. Toole Ave. Monday.

Police were on scene around 8 a.m. Passengers were escorted from the train and there were multiple gunshots fired.

Officers with K9 units boarded the train during the investigation.

Police asked people to avoid the area during the investigation.

Phil Villarreal at KGUN first reported this story.