United States special operations analysts knew that an Afghan building was a hospital days before it was destroyed in a U.S. airstrike on Oct. 3, which killed at least 10 patients and 12 hospital staff, according to a new report from The Associated Press.

Intelligence analysts had been investigating the hospital days before the attack, and had assembled a dossier that included maps with the hospital circled, according to AP. It appears as if analysts suspected the protected medical facility was being used as a base for a Pakistani intelligence operative believed to be coordinating with the Taliban. Intelligence reports seen by AP suggested the hospital was being used by the Taliban as a command and control center and a repository for heavy weapons.

The site was operated by Doctors Without Borders, also known as Medecins Sans Frontieres or MSF, and was attacked in five separate strafing runs over the course of an hour by an AC-130 gunship, despite MSF repeatedly asking U.S. forces to call off the attack. MSF officials said the attack focused on the main hospital building where the emergency room and the intensive care unit were housed, adding that surrounding buildings were not hit, according to RT.

Meinie Nicolai, an MSF official, told AP that the new details suggest "that the hospital was intentionally targeted," adding, "This would amount to a premeditated massacre."

It's not clear whether commanders who authorized the AC-130 gunship attack knew that the site was a hospital.

Nicolai continued: "Reports like this underscore how critical it is for the Obama administration to immediately give consent to an independent and impartial investigation by the International Humanitarian Fact-Finding Commission to find out how and why U.S. forces attacked our hospital."

Doctors Without Borders acknowledged that Taliban fighters had been treated at the facility, but insisted that no weapons were allowed in the hospital, reports The Washington Times.

Nicolai told AP that MSF staff "reported a calm night and that there were no armed combatants, nor active fighting in or from the compound prior to the airstrikes."

Immediately following the incident, the Pentagon claimed the attack had been carried out to protect U.S. troops engaged in a firefight with the Taliban, but it has since retracted that statement and said it was a mistake.