DEVELOPING: At least one student died and 14 other people were hurt Wednesday after a “complex” gun and bomb attack at American University of Afghanistan in western Kabul, police and the head of the city’s hospitals reported, as the military worked for hours to free students and staff inside.

Security forces were conducting a clearing operation to track down the “terrorists,” police spokesman Sediq Sediqqi said, as teachers and hundreds of students took cover in classrooms and safe rooms. Sediqqi said it was not clear if there were one or two attackers.

A car bomb had exploded outside a school for the blind next door before at least one attacker fired at the university campus from that school building, a police officer at the scene told The New York Times.

The U.S. military was assisting Afghan forces who responded to the attack, U.S. Army Colonel Michael T. Lawhorn told Fox News. “These advisors are not taking a combat role, but advising their Afghan counterparts.”

No group immediately claimed responsibility for the attack. The Taliban have been fighting to overthrow the Kabul government for 15 years, and regard foreign civilians as legitimate targets.

Associated Press photographer Massoud Hossaini said he was in a classroom with 15 students when he heard an explosion on the southern flank of the campus. “I went to the window to see what was going on, and I saw a person in normal clothes outside. He shot at me and shattered the glass,” Hossaini said, adding that he fell on the glass and cut his hands. He also tweeted: “Help we are stuck inside AUAF and shooting flollowed by Explo this maybe my last tweets”

The students then barricaded themselves into the classroom, pushing chairs and desks against the door, and staying on the floor. Hossaini and about nine students managed to escape from the campus through a northern emergency gate. “As we were running I saw someone lying on the ground face down, they looked like they had been shot in the back,” he said.

Witnesses and a U.S.-based school administrator told Fox News the gunfire had stopped but security teams were still sweeping the area. Ambulances raced victims to a nearby hospital. Local media reported fires continuted to burn on campus.

The university’s president, Mark English, tells The Associated Press, “we are trying to assess the situation.”

Student Ahmad Mukhtar told the BBC he climbed a 20-foot wall to escape the attack. Another student told AFP over the phone, “We are stuck inside and very afraid.”

Hossaini and students with him took refuge in a house near the campus.

The university was established in 2006 to offer liberal arts courses modeled on the U.S. system. It claims as many as 1,700 students are enrolled there, 40 percent of whom are women.

Two of its professors were kidnapped at gunpoint in Kabul on August 7. The professors were identified as Kevin King, an American, and Timothy Weeks from Australia. Men in military uniforms reportedly abducted them as they traveled between the campus and their home in Kabul. The professors’ whereabouts are unclear.

Fox News’ Rich Edson, Conor Powell, Lucas Tomlinson and The Associated Press contributed to this report.

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