Islamic State militants on Wednesday blew up the Grand al-Nuri mosque of Mosul - the very place from where its leader Abu Bakr al-Baghdadi declared a caliphate after his fighters took control of the mosque and swept through parts of northern Iraq and Syria two years ago.
The destruction of the mosque, which comes ahead of an Iraqi military onslaught on the militants holding on to the mosque was intended to thwart government forces closing on the site from taking over the grand old mosque and its famous leaning minaret.
Iraqi forces have for months been fighting a bloody battle to retake Mosul from the Islamic State, with huge losses to lives and infrastructure.
The Mosul mosque is the symbol of the Islamist's resistance and losing that would prove the nemesis of the militant group. Instead of losing it to government forces and losing its claim to a caliphate, IS fighters packed the building with explosives and blew it up.
The destruction of al-Nuri mosque with its famous minaret that has dominated Mosul's skyline for centuries and is pictured on Iraq's 10,000 dinar bank note, is yet another blow to the city's rich cultural heritage.
The minaret, known as Al Hadba or the hunchback, was under a Unesco rehabilitation programme before the Islamic State took control of Mosul.
ISIS, which has been for years violently erasing a region's history, is a spent force which is morally and physically weakened and is now wielding its remaining power to sow deadly mayhem all around. ISIS has already Killed hundreds of civilians in Mosul.
The recapture of the mosque, built by Nur al-Din Mahmoud Zangi, a ruler who in the 12th century unified Arab forces against crusaders from Europe, would have provided an important symbolic moment for the Iraqi security forces, who have taken heavy casualties.
Earlier on Wednesday evening, Iraqi officers had indicated plans to begin an assault on the mosque on Thursday. But, shortly after the Iraqi military issued a statement announcing that the Islamic State had destroyed the mosque.
IS, on the other had issued a statement through its news agency Amaq claiming that the mosque had actually been destroyed by an American airstrike.
The US Central Command later issued a statement bluntly accusing the Islamic State of destroying the mosque. ''As our Iraqi Security Force partners closed in on the Al Nuri mosque, ISIS destroyed one of Mosul and Iraq's great treasures,'' Maj Gen Joseph Martin, the American commander for the operation, said in the statement. ''This is a crime against the people of Mosul and all of Iraq, and is an example of why this brutal organisation must be annihilated.''
"The Daesh (Islamic State) terror gangs committed another historical crime by blowing up the al-Nuri mosque and its historical al-Hadba minaret," the Iraqi military statement said.