NEW YORK (AP) — Authorities questioned several people early Monday after a car stop in New York City as they worked to determine if there is a connection between several incidents involving explosive devices in two days. An explosion rocked a bustling Manhattan neighborhood Saturday night and an unexploded pressure-cooker device was found blocks away; there was a pipe bomb blast earlier Saturday in a New Jersey shore town; and five explosive devices were found near a New Jersey train station late Sunday.
The New York Police Department says it is looking for a 28-year-old man for questioning in the New York City bombing.
The NYPD tweeted Monday morning that authorities were seeking Ahmad Khan Rahami. He is a naturalized citizen from Afghanistan.
Bill de Blasio says he could be armed and dangerous.
— J. Peter Donald (@JPeterDonald) September 19, 2016
An investigation is leading law enforcement officials to believe that there are signs of a possible terror cell in the two states, according to CNN.
Probe into weekend blasts in NY, NJ leads to signs of a possible terror cell, law enforcement officials say. https://t.co/KJDhyP01wT
— CNN Breaking News (@cnnbrk) September 19, 2016
New York Gov. Andrew Cuomo said it now looks like the Manhattan bombing could be an act of terrorism with foreign connection.
FBI agents and police have converged on an apartment near a New Jersey train station where one of five devices found in a backpack exploded while a bomb squad robot was attempting to disarm it.
It wasn't immediately clear if there was a connection between the dwelling and the blast at the Elizabeth train station at around 12:30 a.m. Monday.
On Sunday night, FBI agents in Brooklyn stopped "a vehicle of interest in the investigation" of the Manhattan explosion, according to FBI spokeswoman Kelly Langmesser.
She wouldn't provide further details, but a government official and a law enforcement official who were briefed on the investigation told The Associated Press that five people in the car were being questioned at an FBI building in lower Manhattan.
The officials spoke on condition of anonymity because they were not authorized to talk about the ongoing investigation.
No one has been charged with any crime, and the investigation is continuing, Langmesser said.
Cuomo, touring the site of Saturday's blast that injured 29 people in Manhattan's Chelsea neighborhood, had said there didn't appear to be any link to international terrorism. He said the second device appeared "similar in design" to the first, but did not provide details.
On Sunday, a federal law enforcement official said the Chelsea bomb contained a residue of Tannerite, an explosive often used for target practice that can be picked up in many sporting goods stores. The discovery of Tannerite may be important as authorities probe whether the three incidents are connected.
Cell phones were discovered at the site of both bombings, but no Tannerite residue was identified in the New Jersey bomb remnants, in which a black powder was detected, said the official, who spoke to the AP on condition of anonymity because the official was not authorized to comment on an ongoing investigation.
Authorities said the Manhattan bombing and New Jersey pipe bomb didn't appear to be connected, though they weren't ruling anything out. The New Jersey race was cancelled and no one was injured.
Late Sunday, more suspicious devices were found near a train station in Elizabeth, New Jersey. Elizabeth Mayor Christian Bollwage said the devices were found in a bag in a trash can by two men who reported seeing wires and a pipe coming out of the package. There turned out to be five devices in the bag. One of the devices exploded as a bomb squad used a robot to try to disarm it. No injuries were reported.
There was no immediate word on whether the devices were similar to those in nearby Seaside Park or New York City.
Officials haven't revealed any details about the makeup of the pressure-cooker device, except to say it had wires and a cellphone attached to it. On Sunday night, police blew up the device, rendering it safe. A forensic examination of the device will be sent to the FBI Laboratory at Quantico, Virginia, police said.
Homemade pressure cooker bombs were used in the Boston Marathon attacks in 2013 that killed three people and injured more than 260.
On Sunday, a team of five FBI agents searched an Uber driver's vehicle that had been damaged in the Manhattan blast, ripping off the door panels inside as they examined it for evidence. The driver, MD Alam, of Brooklyn, had just picked up three passengers and was driving along 23rd Street when the explosion occurred, shattering the car's windows and leaving gaping holes in the rear passenger-side door.
The Chelsea explosion left many rattled in a city that had marked the 15th anniversary of the 9/11 terrorist attacks only a week earlier and where a United Nations meeting to address the refugee crisis in Syria was scheduled on Monday.
Witnesses described a deafening blast that shattered storefront windows and injured bystanders with shrapnel in the mostly residential neighborhood on the city's west side.
As authorities tried to unravel who planted the device and why, one New Yorker, Anthony Stanhope, 40, knew exactly what had just happened.
"I was sitting in my apartment, and all of a sudden I heard a big boom, and I thought to myself wait a minute, it can't be thundering and lightning at this hour, and then all of a sudden car horns went off, and I thought oh my god this isn't lightning, this is too loud - this is a bomb," said Stanhope.