Three separate investigations have confirmed that US warplanes struck a mosque in western Aleppo Province in northwest Syria, killing 56 civilians.

Human Rights Watch, Forensic Architecture, and the geolocation site Bellingcat each reached the conclusion after study of satellite imagery, videos, photographs, and interviews with 14 people with firsthand knowledge of the attack, including four who were in the mosque.

The US attack was on the Omar Ibn al-Khatab Mosque in the village of al-Jinah on March 16, as people gathered for evening prayers.

HRW’s 16-page report finds that statements by US military authorities after the attack indicate that they failed to understand that the targeted building was a mosque, that prayer was about to begin, and that a religious lecture was taking place at the time of the attack.

HRW found no evidence to support the allegation that any armed men, let alone members of Al Qa’eda, were in the mosque.

“The US seems to have gotten several things fundamentally wrong in this attack, and dozens of civilians paid the price,” said Ole Solvang, HRW’s deputy emergencies director. “The US authorities need to figure out what went wrong, start doing their homework before they launch attacks, and make sure it doesn’t happen again.”