The top U.S. commander in Afghanistan, Gen. John Campbell, said Monday that Afghan forces who were reportedly taking fire from the Taliban asked the U.S. to conduct the airstrike that killed 22 at a hospital in Kunduz operated by Doctors Without Borders.

"We have now learned that on October 3rd, Afghan forces advised that they were taking fire from enemy positions and asked for air support from U.S. Forces," Campbell told reporters at a Pentagon news conference, reported The Associated Press. "An airstrike was then called to eliminate the Taliban threat and several civilians were accidentally struck."

Campbell said that U.S. forces were not under attack and the airstrike was not called on their behalf, as was previously claimed by the U.S. military, according to Reuters. "This is different from the initial reports which indicated that U.S. forces were threatened and that the airstrike was called on their behalf," he said.

Three investigations are currently underway, he said, and "if errors were committed, we'll acknowledge them. We'll hold those responsible accountable, and we'll take steps to ensure mistakes are not repeated."

Along with the U.S. military's investigation, NATO and the Afghan government are also conducting investigations, according to ABC News.

While Campbell declined to speak about the rules of engagement for U.S. forces in Kunduz due to the ongoing investigation, he reconfirmed that "the Afghans asked for air support from a special forces team that we have on the ground providing train advise and assist in Kunduz."

"But I think the impression that people got after the first couple days is they were firing directly on U.S. forces, and what I'm telling you today is as I've talked to the investigating officer, as we continue to get updated information, that that was not the case in this place," he said.

The Afghan government said that Taliban fighters were shooting from inside of the hospital, CBS News correspondent Mark Phillips reported, according to AP.

Doctors Without Borders, also known as Medecins Sans Frontieres (MSF), said the Afghan government's attempts to justify the attack are "an admission of a war crime," according to BBC.

Christopher Stokes, the general director of MSF, told AP on Monday that he was "disgusted by the recent statements coming from some Afghanistan government authorities justifying the attack."

Executive Director of MSF U.K., Vickie Hawkins, said the Afghan government's claims are "outrageous" and that "they are to an extent justifying the destruction of a fully functioning hospital."