Gunmen have taken dozens of people hostage after a suicide bomber blew himself up outside a government building in the eastern Afghan city of Jalalabad, according to officials.
Nangarhar provincial government spokesman Attaullah Khogyani told AFP news agency that gunmen had stormed the city's refugees and repatriation department compound after a blast. At least eight people have been wounded, he said.
A gun battle is now under way between security forces and the attackers, provincial officials said.
According to one witness, a passerby named Obaidullah, the attack began when a black car with three occupants pulled up at the entrance to a building used by the department of refugee affairs, and a gunman got out firing around him.
One attacker blew himself up at the gate and two gunmen entered the building, in an area close to shops and government offices, Obaidullah told Reuters news agency.
Minutes later, the car blew up, wounding people in the street, he said.
"We saw several people wounded and helped to carry them away."
Sohrab Qaderi, a member of the local provincial council, said around 40 people appeared to be caught inside the building, which caught fire in the initial stages of the attack.
One hostage had called the security services and told them that the attackers had ordered the people inside not to move, he said.
Provincial government spokesman Attaullah Khogyani said the attack happened during a meeting with NGOs working on refugee-related issues. The head of the department and several other people were taken to safety, he said.
Charlotte Bellis, reporting from the capital, Kabul, said the targeted building is in a "very sensitive area, with the United Nations compound next door and a large hospital on the other side".
"Sporadic gunfire is still being heard," she added.
There was no immediate claim of responsibility for the attack.
The blast is the latest in a series of attacks that hit Jalalabad, the capital of Nangarhar province, in recent weeks, killing and wounding dozens of people.
On Saturday, a series of explosions went off in the city before attackers rushed a medical training centre for midwives. A gun battle that lasted for nearly six hours then ensued, in which two people were killed.
On Monday, Nangarhar provincial health officials said that in the last three months at least 160 people have been killed and more than 490 wounded in attacks on the province.
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