UPDATE: 5:10 a.m. EDT – The U.S. Embassy in Kabul has condemned the “heinous attack” on the American University Of Afghanistan that left 12 people dead, including seven students, three police and two security guards. 

U.S. Ambassador P. Michael McKinley called Wednesday’s attack “a cruel and cowardly act.”

“Our thoughts and prayers are with those killed and injured, as well as with the victims’ families, colleagues, and friends,” McKinley said, in a statement. “We remain strongly committed to the people of Afghanistan who are dedicated to establishing lasting peace and security and building the brightest possible future for their children.”

UPDATE: 11:45 p.m. EDT — The attack on the American University Of Afghanistan left 12 people dead, including seven students, three police and two security guards, police said early on Thursday.

Two militants, who stormed into the university campus Wednesday evening with explosives, were later killed by police. The attack injured 44 people, including 35 students, Fraidoon Obaidi, chief of the Kabul police Criminal Investigation Department, told Reuters.

UPDATE: 12:30 p.m. EDT — The attack at the American University Of Afghanistan may be winding down. War correspondent Mustafa Kazemi tweeted Wednesday that "all students and staff ... are safe now" on the Kabul campus. However, journalist Bilal Sarwary wrote that the incident was ongoing, with seven deaths reported so far.

UPDATE: 12:15 p.m. EDT — At least five people from the American University of Afghanistan have been hospitalized with injuries from the attack, Pajhwok Afghan News tweeted Wednesday

UPDATE: 12:06 p.m. EDT — A student at the American University of Afghanistan told Reuters Wednesday that he couldn't leave the Kabul college amid reports of an attack. "We are stuck inside our classroom and there are bursts of gunfire," Ahmad Shaheer told the wire service.

Meanwhile, police spokesman Sediq Sediqqi told the Associated Press he thought there was only one attacker involved in the raid.

UPDATE: noon EDT — No organization has taken responsibility yet for the ongoing attack at the American University of Afghanistan in Kabul, Voice of America Dari reported Wednesday.

UPDATE: 11:51 a.m. EDT — The American State Department's Bureau of Consular Affairs tweeted Wednesday that people should "exercise caution, avoid unnecessary movement in the area and monitor news for updates" as an incident continued to unfold at the the American University of Afghanistan in Kabul.

The private university was established with the help of the United States Agency for International Development in 2006.

UPDATE: 11:45 a.m. EDT — "Dozens of students and staff" were stuck inside the American University of Afghanistan Wednesday as an apparent attack unfolded at the Kabul campus, TOLO News reported. Members of the Afghan Special Police Force were on the scene, where it's just after 8 p.m. local time.

UPDATE: 11:30 a.m. EDT — Agence France Presse, citing an anonymous official, tweeted Wednesday that "militants" were behind the unfolding attack on the American University of Afghanistan in Kabul. 

TOLO News pointed out that the attack follows an Aug. 7 kidnapping of two professors at the university. One was American, and the other was Australian. At the time, interior ministry spokesman Sediq Sediqqi told AFP that it appeared "a criminal group" was responsible for the abduction.

Original story:

The American University of Afghanistan in Kabul apparently came under attack Wednesday, with witnesses including photographer Massoud Hossaini tweeting that they'd heard explosions and gunfire at the higher education institution.

An anonymous source within the Afghan interior ministry confirmed to Reuters that people had heard shots fired, and journalist Bilal Sarwary tweeted that a police officer on the scene said authorities were "dealing with a complex attack." 

Further details were unclear, but reports of the incident had already begun to dominate social media Wednesday:

The American University of Afghanistan, which opened 10 years ago, has about 1,700 students, according to its website.

This is a breaking news story. Check back for updates.