Prosecutors in El Paso, Texas, will seek the death penalty for the El Paso mass murder and are treating the shooting—which killed 20 people at a Texas Walmart while injuring 26 others—as a “domestic terrorist case.”

“The state charge is capital murder, and so he is eligible for the death penalty,” El Paso County District Attorney Jaime Esparza said on Sunday, Aug. 4. “We will seek the death penalty. The loss of life is so great, we certainly have never seen this in our community.”

Patrick Crusius, 21, allegedly opened fire in the crowded Walmart on Saturday, Aug. 3.

Meanwhile, the feds are also exploring hate crimes and domestic terror charges that are federal death penalty eligible.

“I’ve been in close consultation with U.S. Attorney General [William] Barr. We are conducting a methodical investigation with our partners, a careful investigation but with a view toward bringing federal hate crimes charges and federal firearms charges that carry a penalty of death. We are seriously considering those charges,” the U.S. Attorney for the Western District of Texas John Bash said.

“We are treating it as a domestic terrorism case, and we’re gonna do what we do to terrorists in this country, which is deliver swift and certain justice.”

Crusius, who was taken into custody after the mass shooting, has been cooperating with police, according to authorities.

The suspect was charged with capital murder and is being held without bail Sunday.