An apparent US airstrike on a hospital run by Doctors Without Borders (also known as Médecins Sans Frontières, or MSF) in Afghanistan's Kunduz province killed at least 19 people, including 12 staff members, early Saturday morning.

The bombing began at 2:08am local time and, according to the humanitarian organization, continued for more than 30 minutes "after American and Afghan military officials in Kabul and Washington were first informed by MSF that its hospital was struck." MSF said seven intensive care patients were killed, including three children.

US Forces in Afghanistan acknowledged conducting a strike at 2:15am Saturday morning against "individuals threatening the force."

"The strike may have resulted in collateral damage to a nearby medical facility," US Army Colonel Brian Tribus, a spokesman for US forces in Afghanistan said in a statement, adding that the incident is under investigation.

Doctors Without Borders, which operates in conflict zones around the world, said on Saturday it had communicated the precise GPS coordinates of the hospital to officials in Washington and Kabul multiple times over the past several months, and as recently as Monday, September 29.

A photo provided by Doctors Without Borders shows surgery activities in one of the remaining parts of the hospital in Kunduz in the aftermath of a US bombing. (Photo via MSF/EPA)

At the time of the attack there were 105 patients and 80 staff members at the trauma center. Thirty-seven people, including 19 MSF staff members, were seriously wounded in the attack and many more remain unaccounted for. The most critically injured, the organization says, have been transferred to a hospital in Puli Khumri, a two-hour drive away. All nine staff members killed in the bombing were Afghan, MSF confirmed to VICE News.

"We are deeply shocked by the attack, the killing of our staff and patients and the heavy toll it has inflicted on healthcare in Kunduz," Bart Janssens, MSF Director of Operations, said in a statement on Saturday. "We do not yet have the final casualty figures, but our medical team are providing first aid and treating the injured patients and MSF personnel and accounting for the deceased."

Reached by phone on Saturday morning, Doctors Without Borders spokesman Tim Shenk would neither confirm nor deny reports quoting the Afghan Interior Ministry as saying that 10 to 15 Taliban fighters were hiding in the hospital. Shenk said more information about the incident would be released later on Saturday.

Fire burns at the Doctors Without Borders hospital in Kunduz after a US airstrike. (Photo via MSF/EPA)

Taliban spokesman Zabihullah Mujahid reportedly said there were no militant fighters being treated at the hospital.

US and Afghan forces have been struggling to regain control of the provincial capital since Taliban forces, in one of their biggest coups since the war began 14 years ago, seized the city of Kunduz six days ago. MSF says it has treated 394 wounded since fighting broke out on Monday.

The hospital is near the frontlines of recent fighting in the area. Kunduz police spokesman Sayed Sarwar Hussaini said Afghan security forces were receiving fire from an area adjacent to the hospital on Saturday.

Khodaidad, a Kunduz resident who lives near the facility, reported that Taliban fighters hid behind the walls of the hospital on Friday and fired at government forces.

"I could hear sounds of heavy gunfire, explosions and airplanes throughout the night," said Khodaidad, who, like many Afghans, has only one name. "There were several huge explosions and it sounded like the roof was falling on me."

Video from the aftermath of the bombing showed a bombed-out shell of a building with debris scattered all around. Saad Mukhtar, director of public health in Kunduz, told Reuters that three rooms were still ablaze, and that staff and patients had been forced to evacuate.

"Thick black smoke could be seen rising from some of the rooms," Mukhtar said. "The fighting is still going on, so we had to leave."

Ewan Watson, a spokesman for the International Committee of the Red Cross (ICRC), told VICE News that the Red Cross had several staffers working at the MSF hospital, but they were not present when the early morning bombing occurred and were uninjured.

Watson said NGOs such as ICRC and MSF have regular contact with the US military coalition in Afghanistan in order prevent incidents such as this.

"Healthcare facilities are protected under international humanitarian law, and any attack on them is extremely concerning," he said. "The humanitarian impact is potentially enormous in an area that is dependent on this one hospital."

"Those facilities are absolutely protected under the law," Watson added.

The US embassy in Kabul issued a statement saying it "mourns for the individuals and families affected by the tragic incident."

Nicolas Metri, ICRC's representative in Kabul, confirmed that the organization evacuated all of MSF's international staff from Kunduz by plane on Saturday afternoon.

UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein issued a statement on Saturday calling for "a swift, full and transparent investigation" into the airstrikes.

"This event is utterly tragic, inexcusable, and possibly even criminal," Zeid said. "International and Afghan military planners have an obligation to respect and protect civilians at all times, and medical facilities and personnel are the object of a special protection. These obligations apply no matter whose air force is involved, and irrespective of the location."

NATO Secretary General Anders Fogh Rasmussen issued a statement saying he is "deeply saddened by the tragic incident."

"Doctors without Borders perform extraordinary humanitarian work across the world, including in Afghanistan," he said. "They play an important role in helping create the conditions for a better future for the Afghan people. A US investigation into this tragic incident is under way in coordination with the Afghan government."

MSF said in a statement that the bombing "constitutes a grave violation of International Humanitarian Law."

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