Suicide bombers mounted a strike on a joint U.S.-Afghan base Sunday, sparking a two-hour gun battle that left at least five Afghans dead. American helicopters finally quashed the attack. A truck loaded with explosives crashed into the front of the base, in eastern Afghanistan, around 6 a.m. local time. A second vehicle exploded after being fired on by guards. Six gunmen continued the attack, for which Taliban spokesman Zabiullah Mujahid claimed responsibility. Two Afghan medical students were among those killed.