One dead, one critically injured in shooting at The Oaks mall in Thousand Oaks

A man fatally shot his ex-wife Saturday at her workplace in The Oaks mall in Thousand Oaks before gravely wounding himself in an apparent suicide attempt, police said.

Police said the suspect, a 33-year-old man from the Los Angeles area, arrived at the mall by himself and entered the Paper Source stationery store, 190 W Hillcrest Drive. He argued with his ex-wife before shooting the Thousand Oaks 30-year-old and turning the gun on himself at about 2:20 p.m., according to authorities.

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Emergency medical personnel took the suspect to a local hospital, where he remained in critical condition, according to authorities. His ex-wife was declared dead at the scene.

A gun was recovered at the scene by investigators.

The man and woman have children who were found safe, said Sgt. Eric Buschow, a spokesman for the Ventura County Sheriff’s Office.

“This was a tragic case of domestic violence,” Buschow said.

Aman Sehra, 14, of Simi Valley, was shopping with his younger brother at the Vans store next door to where the shooting took place.

“I heard the gunshots go off and saw everybody rushing into Vans toward the back of the store, trying to hide,” Sehra said.

The mall was reportedly put on lockdown after the shooting, with deputies telling people to shelter in place.

In light of recent mass shootings, Buschow was asked about the process.

The goal of a lockdown is to keep people safe as well as assist investigators with gathering information about the incident, Buschow said. To conduct their investigation, deputies surrounded the mall, performed a security sweep, then went from store to store to interview anyone who witnessed the incident.

“This was a homicide, and we needed to find witnesses to help with the investigation,” Buschow said.

Agoura Hills resident Pia Navarro was inside Nordstrom during the lockdown.

“They’ve locked everything down, so everyone’s pretty calm,” Navarro said at the time.

Also at Nordstrom was Jeffrey Simpson, 17, who was shopping with his mother when an announcement was made about a threat outside the mall.

“I went to Nordstrom to get pants, and the next thing I know, the doors are being sealed,” Simpson said.

He said he and his mom were “a little shaken” but OK. They were in the store for more than an hour, but shoppers were free to move around and employees were helping people stay comfortable and calm, Simpson said.

Those outside the lockdown area were evacuated, according to reports on Twitter, with nearby Ventura County Fire Station 30 set up as a safety zone. After 3:45 p.m., people were allowed back into the mall except for the open-roof shopping area where the shooting occurred, according to the Ventura County Sheriff’s Office.

The mall spans over a million square feet of retail space, most of it enclosed, so many visitors were initially unaware a shooting had occurred.

Peter Birkel was watching the new “Tomb Raider” movie with his family at the mall’s theater while the incident was underway. He and his family were not aware of it until they came out of the movie.

That wasn’t that case with Matt Lemieux, who was working on his computer inside the Coffee Bean, wearing headphones, when he suddenly saw “a whole group of people” running by. His 9-year-old son was at a birthday party in the movie theater, at the end of the mall where the shooting occurred, and he headed there.

“It was creepy,” he said.

Contributing: The Associated Press