The man who fatally shot one detainee at an immigration facility in Dallas and wounded two others had "specifically intended to kill ICE agents," officials said on Sept. 25, citing a trove of writings retrieved from the alleged shooter's home.

Nancy Larson, acting U.S. attorney for the Northern District of Texas, said 29-year-old Joshua Jahn left behind handwritten notes in which he described a "gameplan of the attack" and a desire to give ICE agents "real terror." Larson said Jahn also wished to "minimize any collateral damage or injury to the detainees."

"The tragic irony for his evil plot here is that it was a detainee who was killed and two other detainees that were injured," she said, adding that authorities believe Jahn acted alone.

The latest information comes a day after Jahn allegedly fired at the facility from a nearby rooftop before turning a gun on himself. Authorities say Jahn was found dead of a self-inflicted gunshot wound at the scene. Near his body, investigators located an unspent shell casing with the phrase "ANTI-ICE" written on it, according to FBI Director Kash Patel.

It was the latest shooting to stir a tense national debate over political rhetoric and acts of violence. Two weeks earlier, conservative activist and President Donald Trump ally Charlie Kirk was killed with a single shot during a speaking event at a Utah university. As a result of the Sept. 24 shooting, ICE facilities are ramping up security, officials said.

"This is wrong. Politically motivated violence is wrong," Sen. Ted Cruz, R-Texas, said.

Here's what we know about the shooting so far:

What did Joshua Jahn's writings say?

Larson said that Jahn in his notes expressed "hatred for the federal government" and a wish to "terrorize ICE employees and interfere with their work, which he called human trafficking."

"This, what he did, is the very definition of terrorism," Larson said.

She added that Jahn claimed full responsibility for the attack, writing "Yes, it was just me and my brain."

Jahn also allegedly wrote "good luck with the digital footprint," which authorities are taking to mean Jahn deleted evidence from his devices, according to Larson.

FBI says suspect engaged in 'high-degree' of planning

Joseph Rothrock, special agent in charge of the Dallas FBI field office, described the "significant, high-degree of pre-attack planning" the preceded the deadly shooting.

Rothrock said Jahn searched for information about the ICE facility and how to track the location of ICE agents.

"He knew with a high likelihood that ICE detainees would be transported that morning in the exact location where he was facing from his perch on a nearby rooftop," Rothrock said.

The FBI said the gunman fired at transport vehicles carrying ICE personnel, federal agents and detainees from a nearby rooftop. The gunman also fired multiple shots into the windows of the office building where ICE employees were working. Rothrock said the shooting was a "targeted, ambush style attack on law enforcement."

Rothrock described the gun used in the attack as an 8mm bolt-action rifle Jahn legally purchased in August.

What to know about the facility targeted in the attack

Department of Homeland Security Secretary Kristi Noem identified the targeted facility as a "processing facility," a type of Immigration and Customs Enforcement site playing an increasing role in the White House’s immigration enforcement crackdown, according to experts. Processing or holding centers serve as sites for agents to register detainees and hold them overnight if necessary.

Over 10,000 people have gone through the facility in Dallas so far during fiscal year 2025, according to data shared with USA TODAY by the Transactional Records Access Clearing House, a research group that tracks immigration enforcement data. Data shows that immigration authorities are using the sites as temporary detainment sites more frequently, although detainees are not supposed to be held at the centers for over 72 hours, Long said.

On average, 45 people were held at the facility overnight in July, compared to just one per night during fiscal year 2024, according to info Long’s group obtained via the Freedom of Information Act. At its max, the Dallas site can hold 103 people.

Long, who co-founded the immigration enforcement data group in 1989, said the site is one of just many around the country that play an underappreciated role in deportation proceedings: "This is happening all around," said Long, "and more and more so as more people are getting picked up."

How did the suspect get on the roof?

Larson said authorities believe Jahn used a ladder to access the rooftop from which he launched his attack. She said the suspect was seen driving with a "large ladder" on his car around 3 a.m. on the morning of the shooting.

The gunfire began ringing out around 6:30 a.m. local time, officials said.

Did the gunman work alone?

Multiple officials said Jahn is believed to have acted alone. Jahn in his writings claimed full responsibility for the shooting, Larson said.

She added that investigators did not find evidence of "membership in any specific group or entity."

In his writings, Jahn did not mention any specific government agency other than ICE, Larson said.

Security ramped up at ICE facilities across US

The Department of Homeland Security said it plans to beef up safety protocols at ICE facilities across the country following the fatal shooting in Dallas.

Federal authorities are still investigating the motive of the shooter, but DHS Assistant Secretary Tricia McLaughlin blasted the rising violence against ICE agents. In a statement to USA TODAY she cited "unprecedented acts of violence against ICE law enforcement, including bomb threats, cars being used a weapons, rocks and Molotov cocktails thrown at officers, and doxing online of officers' families."

McLaughlin didn’t provide additional details regarding the new security tactics. Federal facilities are often already guarded and screened by security officers. They're also typically surrounded by fencing, cameras and other security measures.

“The men and women of ICE are fathers and mothers, sons and daughters,” she said. “They get up every morning to try and make our communities safer. Like everyone else, we just want to go home to our families at night. The violence and dehumanization of these men and women who are simply enforcing the law must stop.”

−Lauren Villagran

White House targets ICE notification app, developer responds

White House Press Secretary Karoline Leavitt highlighted reports that the alleged shooter in Dallas had previously used a popular app that flags sightings of immigration officers.

Leavitt criticized CNN for reporting on the app ICEBlock in June and noted its tie to the "leftist lunatic shooter" in Dallas. Patel released details about the shooter’s Internet history, including using "apps that tracked the presence of ICE agents," without naming ICEBlock.

ICEBlock’s developer Joshua Allen defended the service in an interview with USA TODAY in the wake of the shooting. He said the theory that reported sightings of ICE officers led directly to this week’s shooting was far flung.

"Somebody would have to see the enforcement action, be within 5 miles of the report and then somehow say, OK, now they’re done so they’ll be back to the booking facility soon," Allen said. "This is insanity."

Allen said reported ICE activity sightings are purged every four hours and that no predictive analytics are performed to anticipate ICE movements. The app is anonymous and does not track logins. As of this month the app has 1.1 million active users, Allen said. He cited case law upholding the legality of the Waze app, which flags speeding enforcement by police.

Allen said he’s yet to receive any communication from the government.

“I have an amazing legal team, and it makes no sense for them to try to do anything to shut it down,” Allen said. “So that leaves them with these performative statements and trying to bully me.”

−Nick Penzenstadler

Shooter planned attack: FBI

Patel said investigators gathered evidence showing a “high degree of pre-attack planning” in the deadly shooting at an ICE facility in Dallas.

The shooter 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 looked into video footage of the assassination of Charlie Kirk, the FBI director shared on X.

Patel also said investigators recovered a handwritten note reading, "Hopefully this will give ICE agents real terror, to think, 'is there a sniper with AP (armor piercing) rounds on that roof?'"

The writings and search history was retrieved from electronic devices and other items seized from the shooter's home, Patel said.

How did the shooting at the Dallas ICE facility unfold?

According to a City of Dallas database of active police calls, 38 police units responded to a 6:38 a.m. call for assistance at 8100 N. Stemmons Freeway, where the local ICE facility is located.

Authorities said a shooter up on a nearby rooftop fired "indiscriminately" at the building and a van holding the detainees in a sally port.

Three detainees were shot, with one killed and two in critical condition, the Department of Homeland Security said in the latest update. Earlier updates from DHS indicated two victims had died.

Among the victims of the shooting was a Mexican national who was left "seriously injured," the country’s Ministry of Foreign Affairs said in a statement.

Anti-ICE messages found on rounds

Patel said an "initial review of the evidence shows an ideological motive behind this attack."

He posted images on X of ammunition located at the scene, including one inscribed with the phrase "ANTI ICE."

The FBI is investigating the incident as an act of targeted violence, said Joseph Rothrock, special agent in charge of the Dallas FBI field office.

"This is just the most recent example of this type of attack," he said.

Officials condemn violence against ICE amid string of incidents

Government officials in the aftermath of the shooting said that attacks against the immigration agency "must stop."

"While we don’t know motive yet, we know that our ICE law enforcement is facing unprecedented violence against them. It must stop," DHS Secretary Kristi Noem said.

In July, an ICE facility near the Dallas-Fort Worth area was attacked in a shooting that wounded a local police officer. ICE facilities nationwide have been the site of protests, which at times have turned violent with clashes breaking out between federal officers and demonstrators. Last month, the Dallas ICE field issued a shelter-in-place order after a man approached the building and claimed to have an explosive device in his backpack, officials said.

Republicans including Vice President JD Vance have pointed to liberal rhetoric as fueling violent attacks. A study earlier this month by the libertarian think tank Cato Institute found terrorists motivated by extreme right-leaning ideology killed six times more people than those on the opposite side of the political spectrum between 1975 and Sept. 10 of this year.

Contributing: Eduardo Cuevas and Lauren Villagran, USA TODAY

This article originally appeared on USA TODAY: Joshua Jahn, suspect in ICE shooting, targeted agents, hoped to spare detainees: Officials

Reporting by Jeanine Santucci, Christopher Cann and Michael Loria, USA TODAY / USA TODAY

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