At least three explosions were heard at the start of what appeared to be a coordinated attack, Attahullah Khogyani, a spokesman for the Nangarhar provincial governor said. The firefight was taking place in a building housing the state accounts office.
At least four people had been killed and 20 wounded, he said.
The militant attack is the latest in a series across Afghanistan this year. Most have been in the capital Kabul, but in January, gunmen attacked an office of aid group Save the Children in Jalalabad, killing at least five people and wounding 25.
In Sunday’s attack, one attacker appeared to have blown himself up at the gate of the building in the center of the city, allowing the gunmen to enter, Sohrab Qaderi, a member of the provincial council, told Reuters. More explosions were then heard coming from inside the building, he added.
He said at least four attackers, armed with rocket propelled grenades and machine guns still appeared to be fighting police.
There was no immediate claim of responsibility.
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