The lone suspect in the deadly Sept. 24 shooting at an Immigration and Customs Enforcement field office in Dallas has been identified as Joshua Jahn, officials announced on Sept. 25.

Jahn, 29, is accused of indiscriminately shooting at the immigration facility from the rooftop of a nearby law office, killing one detainee and critically injuring two others, Nancy Larson, acting U.S. attorney for the Northern District of Texas, told reporters. Law enforcement officials later found the suspect dead with a self-inflicted gunshot wound.

Officials believe Jahn, of Fairview, Texas, acted alone. No evidence indicates he had membership in any specific group or entity, Larson said.

FBI officials said the shooting was being investigated as an “act of targeted violence” against immigration agents, citing evidence including a shell casing reading "ANTI ICE" and letter that says "Hopefully this will give ICE agents real terror."

No agents were hurt in the attack. Larson called the attack "the very definition of terrorism."

Who is Joshua Jahn?

Little is known at the moment. Jahn is an American citizen who was not an immigrant, officials said.

Jahn’s older brother, Noah Jahn, told NBC the family grew up in Texas. Joshua Jahn, who was unemployed, was planning to move to Oklahoma with their parents, Noah Jahn told the news outlet.

Noah Jahn said Joshua Jahn wasn’t particularly interested in politics and didn’t have strong feelings about ICE as far as he could tell.

Oklahoma voter registration records show Joshua Jahn was a registered independent. He last voted in the Nov. 5, 2024, election.

In 2015, Jahn was charged with delivering marijuana in Collin County, Texas. He eventually pleaded guilty and was issued 5 years of probation and a $500 fine, according to Texas court records.

What kind of weapon did he use?

Jahn used an 8mm bolt-action rifle that he legally obtained in August, said Joseph Rothrock, special agent in charge of the Dallas FBI field office. He brought a ladder on his car that he then used to perch atop the building and shoot at the ICE office just after 6:30 a.m.

DHS described the shooting as indiscriminate by a sniper who shot at the facility and a van at the entrance, where victims were hit inside.

Tricia McLaughlin, assistant secretary for public affairs at DHS, posted images of an office window and framed American flag hit with bullets.

Larson said Jahn's handwritten notes indicate he intended to "maximize lethality" against ICE personnel and maximize property damage, while trying to minimize harm to detainees.

What was suspect’s motive?

Officials have described the incident as an attack targeting immigration agents. He used ICE tracking apps to locate agents, officials said.

According to Larson, Jahn's handwritten notes said ICE personnel were showing up to "collect a dirty paycheck" and that they were involved in "human trafficking."

The suspect also left behind shell casings inscribed with “messages that are anti-ICE in nature,” Rothrock said. On X, FBI Director Kash Patel posted an image of a casing that had “ANTI ICE” written on it.

Since the shooting, investigators recovered other writings as well as search history that shows "a high degree of pre-attack planning," Patel said. The suspect allegedly downloaded a document containing a list of Department of Homeland Security facilities, searched for apps that tracked the presence of ICE agents, sought information on ballistics and searched for video footage of the assassination of Charlie Kirk, according to Patel.

The FBI chief said investigators also recovered a handwritten note reading, "Hopefully this will give ICE agents real terror, to think, 'is there a sniper with AP rounds on that roof?'"

This article originally appeared on USA TODAY: What we know about Joshua Jahn, suspect in Dallas ICE attack

Reporting by Eduardo Cuevas, Nick Penzenstadler and Christopher Cann, USA TODAY / USA TODAY

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