U.S. military officials said several people were wounded in two near-simultaneous bomb blasts outside the main U.S. military base in Afghanistan.
Wednesday's attack occurred at Bagram Air Base, about 60 kilometers north of the capital, Kabul.
A U.S. military spokesman said a car bomb exploded, and moments later a suicide bomber on foot detonated explosives near the base's main gate.
Details of the casualties were not immediately confirmed.
In other violence, military officials said a roadside bomb killed three Canadian soldiers in southern Afghanistan's Kandahar province Tuesday.
Some information for this report was provided by AP and Reuters.