At least four persons were killed and as many as 20 were injured in a gunbattle between security forces and a group of militants in Afghanistan's Jalalabad on Sunday.
Afghan security forces have struggled to combat the Taliban and ISIS since the U.S. and North Atlantic Treaty Organisation formally concluded their combat role in the country in 2014, shifting to a support and counterterrorism mission.
A auto bomb was detonated at the entrance to the state accounts office before a group of about six attackers armed with machine guns and rocket-propelled grenades rushed the building, the officials said.
No one immediately claimed responsibility for the attack.
Militants have staged several attacks across Afghanistan this year. Witnesses said the explosions had caused carnage among passers-by.
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France's military is active in the US -led coalition against the Islamic State group in Iraq and Syria. Among the four hospitalized, two were in serious condition and two others sustained minor injuries.
The provincial governor's spokesman also added that the security forces managed to rescue at least forty two people, including civilians and government workers.
Jalalabad is the capital of restive Nangarhar, which borders Pakistan. Both the Taliban and a local affiliate of the Islamic State (IS) extremist group have carried out numerous attacks in Nangarhar Province. Officials are concerned that a low voter turnout will undermine the credibility of the poll.
Operation Al Khandaq will target USA forces and "their intelligence agents" as well as their "internal supporters", a Taliban statement said in late April.
Nine journalists, including AFP's chief photographer in Kabul Shah Marai, were among the 25 people killed in a double suicide blast claimed by ISIS in the capital on April 30.
Heavy security forces arrived at the spot of the attack.