Militants have attacked a midwife training center in the city of Jalalabad in eastern Afghanistan, officials said.
A number of explosions have been reported and gunshots could be heard in the area of a dormitory for trainee midwives, reports said.
RFE/RL's Radio Free Afghanistan quoted witnesses as saying that a suicide bombing had taken place in the area.
Attaullah Khogyani, the provincial government spokesman, said some of the students had been evacuated from the building. Others were still trapped in the building, reports said.
He said the explosion was reported in the third police district of Jalalabad in the eastern province of Nangarhar.
Khogyani said three wounded civilians have been taken to hospital.
"The Afghan security forces have cordoned off the area and [have] launched an operation to gun down the attackers," he added.
Provincial health department spokesman Inamullah Miakhil confirmed its midwife center had been attacked.
No one claimed responsibility for the attack.
Both the Taliban and the Islamic State (IS) extremist group have carried out numerous attacks in Nangarhar Province.
The last major attack in Jalalabad happened on July 11 when gunmen attacked an education department compound in the city, killing at least 11 people.