U.N. fire officials evacuated the three basement levels of the landmark 39-story U.N. headquarters building Friday evening to investigate a suspect car in the garage.

The New York Police Department's bomb squad was called in to investigate.

An Associated Press reporter at the scene in the third basement of the garage saw U.N. police officers with sniffer dogs along with U.N. fire officials, New York police officers, a vehicle belonging to the bomb squad and other police emergency units.

A U.N. fire safety official went on the intercom and told all U.N. staffers in the building: "There is a condition in the third basement garage that is being investigated."

He gave no details but said that as "a precautionary measure" three basement levels had been closed.

The rest of the U.N. headquarters building remained open.

U.N. Secretary-General Ban Ki-moon was attending a closed meeting on Myanmar on the first basement level shortly before the announcement. He returned to his 38th floor office.

A U.N. sniffer dog apparently smelled something suspicious during a sweep of the garage about the time Ban was emerging from the meeting to talk to reporters, a U.N. official said, speaking on condition of anonymity because he was not authorized to speak publicly.