A hand grenade blast claimed the life of one civilian and injured 52 others including three foreign service-members in Kunar province east of Afghanistan Tuesday, provincial Police Chief Abdul Jalal said, Xinhua reported.
"The incident occurred in the provincial capital Asadabad at 08:30 a.m. local time (GMT0400) when a man threw one hand grenade near a convoy of U.S. troops killing one civilian on the spot," Jalal told Xinhua.
Jalal added that 49 more civilians and three foreign nationals who served as advisers to Afghan police were injured.
However, he could not provide more details, saying a three- member commission has been constituted to investigate the issue.
Meantime, witnesses, according to media reports, said one U.S. soldier threw the grenade as a response to a sudden tyre burst of his vehicle.
Kunar, a mountainous province border Pakistan's lawless tribal area of Bajawar has been the scene of militants' activities for the past couple of years.
No groups or individuals have claimed of responsibility while Taliban fighters have vowed to step up activities this year in Afghanistan.