Several detainees were shot at a U.S. Immigration and Customs Enforcement field office in Dallas on Wednesday morning, according to a spokesperson from Homeland Security who spoke to the Associated Press.

Police believe the shooter opened fire from a nearby building at approximately 6:40 a.m. One person died on the scene, while two others were transported to hospitals.

The suspect died by suicide, according to Homeland Security Secretary Kristi Noem. No agents were injured, the DHS spokesperson told AP.

Texas Gov. Gregg Abbott called the shooting an “assassination.”

Texas Department of Transportation cameras showed heavy police traffic and emergency vehicles lined up around the facility, and crews observed SWAT trucks responding early Wednesday morning.

Dallas Bureau of Alcohol, Tobacco, Firearms and Explosives and FBI agents are also assisting, the agencies confirmed.

Assistant DHS Secretary Tricia McLaughlin said the shooting came as ICE personnel face a “1000% increase” in assaults. The department has not provided hard data to back that number.

Vice President JD Vance called the shooting an “obsessive attack on law enforcement.”

Threats, allegations at Dallas-area ICE facilities

A man threatened ICE officers and claimed to have a bomb at the same field office on Aug. 26, according to DHS. The suspect, a 36-year-old American citizen, was arrested and charged with making terroristic threats.

In recent months, federal lawmakers and activists have alleged “inhumane” treatment of detainees at the field office, including the withholding of food, water, air conditioning or proper sleeping quarters.

About 40 miles southwest of Dallas at the Prairieland Detention Center in Alvarado, a July 4 “planned ambush” wounded a police officer and led to the arrests of 10 people involved.

The attackers set off fireworks, vandalized structures with phrases like “ICE pig” and “traitor” and attacked a responding police officer.

This is a developing story. Refresh for updates.