One person was killed and three others were injured in a shooting Wednesday evening at the Cielo Vista Mall in El Paso, Texas, police said.

Two people, both male, are in custody and there is no longer a threat to the public, interim El Paso Police Chief Peter Pacillas said at a news conference Wednesday night.

It was chaotic. People did flee. They were scared, police Sgt. Robert Gomez said.

Two injured males were brought to the University Medical Center of El Paso in critical condition, the hospital told CNN. The condition of the third injured person, a male who Gomez said was also hospitalized, is unclear.

The mall is immediately adjacent to a Walmart where a shooting in 2019 killed 23 and left nearly two dozen more injured. The 24-year-old gunman pleaded guilty to 90 federal charges last week as part of a plea deal.

So far this year, there have been more than 70 mass shootings across the United States, according to the Gun Violence Archive. Both CNN and the archive define a mass shooting as a shooting that injured or killed four or more people, not including the shooter.

After Wednesday's shooting happened around 5 p.m. local time, an off-duty officer who was working security in one of the mall's stores arrived at the scene within minutes and took a person into custody, Pacillas said. He did not say when, where or how the second person was apprehended.

Multiple law enforcement agencies, including El Paso police, the Texas Department of Public Safety and US Border Patrol, responded to the scene after several people called 911 to report an active shooter, police said.

The scene was later secured and authorities worked into the night to clear the building and begin a preliminary investigation, police said.

Investigators preliminarily believe the shooting took place around the mall's food court, Gomez said. To assist with the investigation, the FBI has created a website for people to submit photos and video of the incident.

Brandon Chavez, 29, said he was working in the Buckle clothing store across from the food court when Wednesday's shooting happened. He helped customers and other employees barricade inside the store and took people into the stock room as they waited to be able to come out, he told CNN.

Chavez also was working at the mall when the 2019 shooting happened in the neighboring Walmart, he said, adding he sheltered there with others at that time, as well.

Robert Gonzalez was also at the mall on Wednesday and during the 2019 shooting. He saw people running to the exit Wednesday, he said, and videos he took show several mall storefronts closed with their security gates down and several law enforcement vehicles outside.

I was working (at the mall) the last time this happened with the Walmart shooting so it just brought back bad memories, he said.

Gonzalez said he was able to make it safely to his car, where he was waiting to leave as he spoke with CNN.

A reunification center has been set up at nearby Burges High School, where people who are unable to contact their loved ones may go for information, Gomez said.

This is a developing story and will be updated.