UPDATED 3:50 P.M. ET: Journalist Mustafa Kazemi who is in Kabul tweeted around 1 p.m. ET that police forces had killed the gunmen and the attack was over, but later updated around 3:30 p.m. that the brother of a person still stuck inside a building at the American University of Afghanistan informed him that combat was continuing on campus. 

Kazemi also tweeted that a suicide bomber had been intercepted before we was able to detonate his explosives:

The Associated Press reported around 3:30 p.m. ET that the count of people injured in the attack was up to 18.

Original story below.

Early Wednesday afternoon, multiple reports emerged that the American University of Afghanistan in Kabul was under attack by gunmen. Witnesses also reported explosions and fires on campus that trapped hundreds of students and professors inside. American University president Mark English confirmed to the Associated Press that an attack was underway.

CBS journalist Ahmad Mukhtar was on the university's campus when the attack began and tweeted out that he heard a "boom." He then escaped with some friends, but other friends and professors were still trapped inside:

Massoud Hossaini, a photographer for the Associated Press who was also in a classroom along with 15 students when the attack started, recounted her experience for AP. "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, a Pulitzer-prize winner, said. "As we were running I saw someone lying on the ground face down, they looked like they had been shot in the back." The AP further reported that Hossaini and nine students escaped to a house near campus.

Reuters reported that Afghanistan's senior interior ministry official confirmed that elite Afghan forces had surrounded the campus, adding that according to initial reports, the attack was coming from several gunmen, some of whom were wearing suicide vests. Afghan forces exchanged fire with the gunmen, according to ABC News

ABC further reported that the attack has stopped, as confirmed by local police. 

The American University of Afghanistan was targeted before only two weeks ago, according to the AP. Two members of the university's staff were kidnapped from their car by unidentified gunmen. The two men have still not been recovered and their location is not known.