Sources: Police looking to talk to man seen on surveillance in both Chelsea explosion locations

CHELSEA, Manhattan (WABC) --
The New York City Police Department said the explosion in Chelsea Saturday night that injured dozens of people was "definitely" a bomb, with components indicative of an IED being found at the blast site.

Now, multiple law enforcement officials tell ABC News that there is a man who is seen on surveillance images recovered from both the 23rd Street and 27th Street locations who police would like to talk to. Police are not yet classifying him as a person of interest, and have not identified who he is.

Law enforcement sources tell also ABC News that the explosives in both Chelsea and in New Jersey were set off by cell phones. Multiple law enforcement officials tell ABC News that investigators are exploring the possibility the two explosions in Chelsea and Seaside Park are linked to the same bomber or bombers by what appear to be similar types of cell phones. ABC News is cautioned that this is only a line of inquiry and not a conclusion. The probes remain separate but coordinated.

NYPD Commissioner James O'Neill said investigators are working to determine the motivation behind the bombing and find out who did it. He described the multi-agency effort as a "very complex post-blast investigation."