A suspect who wrote “ANTI-ICE” on an unused bullet killed one person and wounded two others on Wednesday at an Immigration and Customs Enforcement (Ice) field office in Texas, US, before taking their own life, officials said.

FBI director Kash Patel posted a photo on X of what he said were the suspect’s unspent shell casings that showed one with the words “ANTI-ICE” written along the side.

“While the investigation is ongoing, an initial review of the evidence shows an ideological motive behind this attack,” Mr Patel wrote.

At a news briefing in Dallas, officials disclosed the existence of the shell casings but emphasised that the investigation was still in its early stages.

Authorities were treating the attack as an “act of targeted violence”, Joseph Rothrock, special agent-in-charge of the FBI’s Dallas field office, told reporters.

Officials did not offer any details about the suspect’s identity.

The suspect opened fire on the office from an adjacent building around 11.40am Irish time, police said. Two people were transported to a hospital with gunshot wounds, while a third person died at the scene.

Law enforcement officers were not injured in the shooting, officials said. The attack took place at an Ice field office, not a detention facility, where Ice officers conduct short-term processing of recently-arrested detainees.

“It looked like it might have been a sniper or some sort of a long-form shot,” Tricia McLaughlin, a spokeswoman for the US department of homeland security, told Fox News earlier on Wednesday.

The incident comes two weeks after the shooting death of conservative activist Charlie Kirk by a sniper during an event in Orem, Utah, which fuelled fears of a new wave of political violence in the United States.

President Donald Trump, vice-president JD Vance and other administration officials have blamed, without proof, liberal organisations for fomenting unrest and encouraging violence against the right.

On Monday, Mr Trump signed an executive order declaring the anti-fascist movement antifa as a domestic “terrorist organisation” despite the fact that there has been no evidence made public linking antifa to Kirk’s death.

The Trump administration’s aggressive use of Ice agents as part of its crackdown on undocumented immigrants has sparked outcries from Democrats and liberal activists. Ice detention facilities have increasingly become sites of conflict, with heavily armed agents deploying pepper ball guns, tear gas and other chemical agents in clashes with protesters.

An Ice facility in suburban Chicago, where protesters have gathered daily since a Trump administration immigration surge began earlier this month, erected fencing on Monday after several demonstrators, including the mayor of Evanston, Illinois, were injured in a clash with agents last week.

Wednesday’s attack was the third shooting this year in Texas at a department of homeland security facility. A police officer was shot in a July incident at an Ice detention centre in Prairieland, and a 27-year-old Michigan man was shot dead by agents after opening fire on a US border patrol station in McAllen in July. – Reuters