FBI agent explains what police are looking for after Lower Manhattan blast

Federal agents and city police took a suspect into custody outside 26 Federal Plaza after a blast around 8:30 a.m. Monday sent smoke across the sidewalk between Worth and Lafayette streets in Lower Manhattan. The building houses U.S. Immigration and Customs Enforcement, the FBI and immigration court operations, making the scene one of the most sensitive federal corridors in New York.

FBI Director Kash Patel said an individual "deployed an incendiary device" outside the building, and he said two minor injuries were reported. Other local reports put the number of injured at three. The FBI said the New York Joint Terrorism Task Force was handling the case, while the New York Police Department moved in after video showed smoke and officers appearing to detain a person on the ground.

The first hours of a case like this are where investigators try to lock down the timeline. They focus on surveillance footage from the block, the path the suspect took and the physical remnants left behind by the device. In this case, the scene already offered several clues to test against that record. A wagon at the site bore a sign reading "ICE off our streets," and fireworks were loaded into it, details that help detectives match objects seen in video with what was recovered at the plaza.

Tim Gallagher, the former FBI special agent in charge of the Newark and Washington field offices, now managing director, chief security officer and co-lead for physical security and threat mitigation at Nardello & Co., has said law enforcement has to remember that "our enemy is ever-evolving." In a fast-moving blast investigation, that means looking beyond the sidewalk and into the suspect's movements, any digital trail, and whether the device was assembled in a way that points to planning or improvisation.

Federal Plaza has carried that security weight for years. In 2017, an FBI agent was injured there when a flash grenade prematurely detonated, and the 1993 World Trade Center bombing remains a major benchmark in New York counterterrorism history. That history is part of why a single morning explosion outside 26 Federal Plaza can draw city police, federal agents and terrorism investigators within minutes.