Authorities said a Korean-American postal employee from Illinois emptied a seven-shot pistol in front of the United Nations Headquarters Thursday.
The man is now in FBI custody.
Authorities said he threw leaflets on the ground and was quickly tackled by US secret service agents who were there protecting the visiting president of Cyprus.
There were no injuries, but shots hit at least two upper floors of the UN building. Several of them narrowly missed UN employees inside the secretariat building.