Footage released Friday shows the destruction of Mosul's al-Nuri mosque and its iconic leaning minaret known as al-Hadba at the hands of ISIS.
Iraq's Ministry of Defense said that the mosque was blown up by ISIS fighters on Wednesday night.
The mosque, which is also known as Mosul's Great Mosque, is where ISIS leader Abu Bakr al-Baghdadi declared a so-called Islamic caliphate in 2014 shortly after Mosul was overrun by the militants. The minaret that leaned like Italy's Tower of Pisa had stood for more than 840 years.
ISIS fighters initially attempted to destroy the minaret in July 2014. The militants said the structure contradicted their fundamentalist interpretation of Islam, but Mosul residents converged on the area and formed a human chain to protect it. ISIS has demolished dozens of historic and archaeological sites in and around Mosul, saying they promoted idolatry.
"This is a crime against the people of Mosul and all of Iraq, and is an example of why this brutal organization must be annihilated," U.S. Maj. Gen. Joseph Martin, the commander of coalition ground forces in Iraq, said in a written statement.
"The responsibility of this devastation is laid firmly at the doorstep of ISIS," he added.
The fight to retake Mosul was launched more than eight months ago and has displaced more than 850,000 people. While Iraqi forces have experienced periods of swift gains, combat inside the city has been grueling and deadly for both Iraqi forces and civilians.