An incendiary device went off outside a federal building in Lower Manhattan Monday morning, and a suspect has been taken into custody, the FBI said. The FBI New York Joint Terrorism Task Force is investigating the incident.
The incident happened outside 26 Federal Plaza, a building that houses dozens of agencies including the FBI, Immigration and Customs Enforcement, and U.S. Citizenship and Immigration Services.
The sound of an explosion had authorities running to the steps leading into the building. They found a man with an airsoft rifle, carbon dioxide cartridges, halogen lighting and a helmet, multiple law enforcement sources said.
Preliminary information indicates fireworks in a garbage can exploded, senior security sources told CBS News. The fire department responded to put out flames, and a man was taken into custody.
CBS News New York 
Sources described the suspect as an anti-ICE activist. They said he had a small cart with him with the slogan “ICE off our streets” written on it.
“At this time, our Joint Terrorism Task Force is investigating this as an anti-government attack on a federal facility,” said FBI official James Barnacle.
BB or airsoft guns, commercial-grade fireworks found
The suspect was carrying two types of guns that appeared to be realistic-looking BB guns or airsoft guns, according to preliminary information. One of the two was some type of long gun carried in a grocery cart, law enforcement sources told CBS News.
CBS News law enforcement analyst Richard Esposito described the materials as “things you might use in paintball-type events.”
The sources said an initial review found no shots were fired.
CBS News New York 
4 minor injuries at 26 Federal Plaza, firefighters say
Firefighters said four people had minor, non-life-threatening injuries, and one was transported to a local hospital.
Video from the scene showed heavy smoke in front of the building and law enforcement arresting a man.
New York City Mayor Zohran Mamdani called the incident “deeply disturbing.”
“My team is in touch with the NYPD, and we will support the federal investigation. Our administration will continue to ensure that every New Yorker is safe in their city — and hold accountable any who threaten that,” he wrote, in part, on social media.
Police said people should expect traffic delays, mass transit disruptions and road closures near Worth Street and Lafayette Street. They are urging people to avoid the area.