An armored vehicle carrying U.S. personnel deliberately crashed through a closed gate at the medical compound hit by a U.S. air strike in northern Afghanistan two weeks ago, the military acknowledged Monday.

Navy Capt. Jeff Davis, a Pentagon spokesman, said Monday that the incident – which occurred Thursday -- was a mistake. He said that the Afghan vehicle carrying U.S. personnel drove through the closed gate to gain access to the compound run by an international charity called Doctors Without Borders.

Davis said the military believed incorrectly that none of the charity's personnel were present. He said the visit was to assess the "structural integrity" of the building damaged in the Oct. 3 attack, which killed 22 people.

The U.S. military has offered to repair the damage from the incident, but according to Davis, the Doctors Without Borders staff present at the facility were “understandably not happy” when the vehicle rammed the gate open.

An initial casualty assessment report on the air strike and whether civilians were killed is expected next week, Davis said.

He added that the report will include answers to "were there civilian casualties and did we cause them?"

Fox News’ Jennifer Griffin and The Associated Press contributed to this report.