Two gunmen were killed at American University of Afghanistan in Kabul early Thursday, hours after an attack launched against the institution, authorities said.
The attack began Wednesday evening when a car bomb was detonated at the front gate of the university and multiple gunmen forced their way inside, Afghan Interior Ministry spokesman Sediq Sediqqi said.
Special forces responded and engaged the gunmen, and killed two attackers, a senior security official at the scene said at around 4 a.m. local time (7:30 p.m. Wednesday ET).
More than 30 students and staff have been rescued, the security official said. A witness who escaped the attack said he what appeared to be at least one person shot dead.
Several special forces were killed and injured and a search continued for any other possible attackers, the senior security official said.
Dejan Panic, the program director at Kabul's Emergency Hospital, told The Associated Press that 18 people wounded in the attack, including five women, had been admitted. He said three were "seriously" wounded, probably from automatic gunfire.
"We have been notified of a complex attack on the American University on Darul-Aman Road," the commander of the Kabul police's quick reaction force told NBC News after receiving reports at about 7:30 p.m. (11:00 a.m. ET).
A senior U.S. defense official said American military troops who are advising the Afghans have been on site at the university but are not taking part in a combat role.
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A student told NBC News that he had just walked out of a class with friends when he heard gunfire and they started running toward the cafeteria. A "massive explosion" threw them to the ground.
"We got up, and in the midst of dust ... kept running to the back of the building and climbed the walls and jumped down on the street," he said, adding that he hurt his back and may have fractured his foot.
Pulitzer Prize-winning photographer Massoud Hossaini tweeted that he was at the university and heard shooting and an explosion:
Hossaini later told NBC News he was inside an English class with other students when a "big explosion" was heard the seemed to come from south of the building.
He went to investigate and saw trees on fire, and a man walking who suddenly raised a gun and pointed it in his direction. Hossaini ducked and went back to the classroom and the students used desks to barricade the door to the second-floor classroom.
Then they heard shooting on the first floor, Hossani said.