A police official said the blast was near a major traffic circle just outside the main entrance to the embassy and the headquarters of the NATO-led International Security Assistance Force (ISAF) in Kabul.
Reuters witnesses heard alarms blaring across the sprawling compound soon after the blast.
The attack came a day after a suicide bomber attacked a German convoy entering an ISAF at the city’s international airport.
The U.S. troops are scheduled to withdraw from Afghanistan in 2014.
Source: NDTV and Reuters