NEW YORK -- Police searched on Friday for possible witnesses, including an unidentified jogger and a cyclist, in the investigation of the early morning explosions outside a midtown Manhattan office building that houses the British Consulate.
Murky images taken from security cameras showed the female jogger and perhaps two pedestrians passing near the entrance to the building on Thursday shortly before the blasts, police said. The cyclist and a yellow cab appeared about the time the two makeshift grenades went off, shattering a large glass panel but causing no injuries.
Investigators were reviewing and enhancing 17 video surveillance tapes from 15 locations, New York Police Department chief spokesman Paul Browne said.
As of late Friday, no suspects had been identified. Nor had police been able to locate any witnesses, despite appeals for them to come forward and hours of canvassing by investigators.
The explosions occurred just as Britons went to the polls in a national election, fueling speculation that the consulate -- one of several tenants in the building -- was targeted.
But Browne said the motive of the explosions and intended target remained unknown. He dismissed a claim of responsibility by a little-known group, Soldiers of Levant, saying it "has a practice of taking credit for acts it did not commit."
The devices were described as replica grenades, normally sold as novelty items on the Internet and elsewhere, which were stuffed with gunpowder and lit with a fuse.
Investigators said they believed the grenades were placed in a concrete planter outside the building or were thrown by someone shortly before the explosions. One grenade apparently blew off a chunk of the planter while the other shattered the window, police said.