Doctors Without Borders are demanding a full, independent inquiry into Saturday’s incident on the outskirts of the northern Afghan city of Kunduz, in which a US warplane repeatedly attacked a Doctors Without Borders hospital, killing 22 people within, including 12 members of staff and 10 civilian patients.

Though Doctors Without Borders informed the US and Afghan governments immediately upon the first strike near the hospital, they reported being repeatedly and precisely targeted by the warplane for over 30 minutes after that, and are saying that the presumption of any investigation should be that a war crime was committed.

The Pentagon insists they are conducting a full investigation themselves. Defense Secretary Ash Carter says the situation is “confused,” but that they would hold anyone responsible if the bombing is “something they shouldn’t have done.” He refused to rule out further strikes, saying it was up to Gen. Campbell to do whatever he thinks is appropriate. The hospital has been closed and the workers evacuated.

The Afghan government is claiming attacks on the hospital were “retaliation” and that the site was actually a “Taliban base.” Doctors Without Borders has rejected this claim as absurd, noting they’ve been at that site for some time, and it was well known it was a hospital.

The UN Human Rights Chief also declared the attack “inexcusable,” saying that if it is confirmed that the attack was deliberate it would amount to a war crime. The US has ruled out ever allowing any of their soldiers to be charged with war crimes under any circumstances, and has a law on the books dating back to 2002 allowing a military invasion of the Netherlands to stop the International Criminal Court from carrying out such charges.

Pentagon investigations are rarely particularly credible, and usually end with some sort of blanket excuse and statement of “regret,” and any punitive action tends to be taken against only the lowest ranked personnel possible.