The American University of Afghanistan in Kabul is under attack.
The number of students and professors inside are unknown, as is the identity of the attackers.
Massoud Hossaini, a photographer for The Associated Press, tweeted that he is trapped inside.
"Help we are stuck inside AUAF and shooting flollowed [sic] by Explo this maybe my last tweets," he wrote.
Two professors at the university -- one American and one Australian -- were abducted at gun point earlier this month.