Police spokesman Paul Browne says the move wasn't prompted by a specific threat in the city. But the nation's biggest police department is taking no chances as it learns more about the attack on Kabul's Inter-Continental Hotel, which is frequented by foreigners.
Insurgents attacked the hotel with suicide bombers, machine guns and rocket-propelled grenades late Tuesday Kabul time.
Two NATO helicopters later fired rockets that killed gunmen on the rooftop of the hotel.
The Taliban claimed responsibility for the attack, which comes nearly a week after President Barack Obama announced he would end the American combat role in Afghanistan by the end of 2014.