Police and bomb squad agents are investigating a suspicious vehicle near Union Square in New York City on Thursday. A pedestrian reportedly saw two gas canisters inside the parked car and called police. Streets and buildings nearby have been evacuated as a precaution, and bomb squad agents with a robot and emergency personnel are still working at the scene. Meanwhile, authorities investigating the attempted bombing in New York's Times Square have arrested three men during searches over four US states. The justice department said they were being held over alleged immigration violations after raids in Maine, New York, New Jersey and Massachusetts. The US attorney general said the three were linked to a man already charged with the attempted attack on 1 May.