— -- As many as five people were taken into FBI custody Sunday night in connection with Saturday's explosion in Manhattan's Chelsea neighborhood, after a traffic stop on the Belt Parkway in Brooklyn, just off the Verrazano–Narrows Bridge, which connects the New York City boroughs of Brooklyn and Staten Island, law enforcement sources told ABC News.
The FBI's New York field office said a traffic stop was conducted but did not elaborate. "We did a traffic stop of a vehicle of interest in the investigation. No one has been charged with any crime. The investigation is continuing," read a tweet from the office.
According to The Associated Press, the individuals were taken to an FBI building in lower Manhattan to be questioned.
The FBI may be looking for additional suspects, the sources told ABC News.
As ABC News previously reported, multiple law enforcement officials told ABC News that investigators are exploring the possibility that the New York explosion and one earlier that day in New Jersey are linked to the same bomber or bombers, because of what appear to be similar types of cellphones.
On Sunday night multiple law enforcement officials told ABC News that police would like to talk to a male seen on surveillance images recovered from both 23rd Street in Manhattan, where the explosion occurred, and 27th Street, where an unexploded second device was found.
Police have not identified the man and have not characterized him as a person of interest. It is also unknown if that man is related in any way to those taken into custody Sunday night.
The explosive device in New Jersey and the one that caused the blast in New York City were both set off with cellphones, according to two law enforcement officials who have been briefed on the case. The unexploded device also had a cellphone connected to it.
Authorities cautioned that this is only a line of inquiry and not a conclusion. The probes remain separate investigations, the FBI and officials in New York said.
"Just because you have one thing in common doesn't mean the devices are similar," one official told ABC News.
The explosive devices looked very different: The one in New Jersey consisted of pipe bombs, and the one in New York was not.
The video below was posted by Terri restaurant on West 23rd Street, 176 yards east of where the explosion took place. A boom is heard.
New York City Mayor Bill de Blasio said at a press conference Saturday that there was at that point no evidence linking the Saturday night blast in Manhattan's Chelsea neighborhood to the explosion earlier that day, in Seaside Park, New Jersey, along the route of a planned 5K charity run for military service members. But, he said, the possibility of a connection "will continue to be considered ... [We] are not taking any options off the table."
"We know there was a bombing," he said. "We will be very careful and patient to get to the full truth here.
"Was it a political motivation, a personal motivation? What was it? We do not know that yet," de Blasio said.
The New York City explosion, which injured at least 29 people, occurred around 8:30 p.m. in an area frequented by shoppers and diners. All of those injured have been released from hospitals, de Blasio said.
In a block-by-block search after that blast, two former state troopers found a second device on 27th Street between Sixth and Seventh avenues, said James O'Neill, the city's police commissioner. That device, using a pressure cooker, was in a white plastic bag with tape, wiring and a cellphone or other electronic device.
The second device was sent to the NYPD's bomb squad facility in the borough of the Bronx, and on Sunday around 7:45 p.m., the NYPD spokesman J. Peter Donald tweeted, "NYPD and FBI Bomb Technicians rendered the device safe. A forensic examination of the device and its components will be conducted at the FBI Laboratory at Quantico, Virginia."
"We have two separate crime scenes," O'Neill said, adding that the FBI and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives are involved in the investigation.
O'Neill said officers have recovered video from both scenes and are continuing to canvass for witnesses and additional video.
Cuomo said that while no international group has claimed responsibility for planting the explosive device, any bomb exploding in New York was terrorism "generically."
Surveillance video from the site of the blast shows the explosion and indicates that an object containing the explosive device was intentionally left next to a construction trash container.
In one video obtained by police, a man is seen crossing the street in the vicinity of where the explosive device appears to have been left. The trash container was blown into the street by the force of the blast.
The New Jersey blast took place in Seaside Park on Saturday morning along the route of a planned 5K charity race to benefit U.S. Marines and sailors. Because of delays starting the run, the explosion occurred when not many people were nearby.
ABC News' Michael Edison Hayden contributed to this report.
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