Multiple SWAT teams have been called to a serious active shooting at a Walmart near the Cielo Vista Mall in El Paso, Texas, and three people are reportedly in custody, the mayor of the city said.

The shooting that happened at about 1 p.m. local time in a commercial area near the Cielo Vista Mall has resulted in multiple fatalities, with at least 18 people injured and taken to local hospitals, law enforcement officials said.

Law Enforcement Today reported that according to sources close to the scene, as many as 22 people are dead including four children. 

It’s not yet clear how those in custody are connected to the shooting.

Witness Vanessa Saenz, who had her 1-year-old son with her, spotted the alleged shooter, told Fox News that the man was holding a dark rifle while pointing and shooting at people. She said the suspect was wearing a black shirt, cargo pants, and had ear muffs on his ears.

“He was just pointing at people and just shooting straight at them,” Saenz said. “I saw three to four [people] fall to the ground.”

Texas Lt. Gov. Dan Patrick told Fox News that one suspect was a 21-year-old man. Local reports indicated the suspect is Patrick Crusius, of Dallas.

Authorities have not confirmed the exact number but University Medical Center got at least 10 victims with “level one” injuries, which is the most serious level, spokesman Ryan Mielke said. 

El Paso police are reporting that there is no imminent threat but the scene is still active. People are also urged to stay away from the area around 1-10 and Airway to Hawkins.

Witnesses respond to the shooting on Twitter.