The Islamic State in Iraq and the Levant (ISIS), the Sunni Muslim insurgent group who swept across northern and western Iraq earlier this year, menacing Baghdad in the process, has commenced the systematic destruction of the country's cultural treasures.

The Wall Street Journal reported that the group had destroyed a mosque in the northern Iraq city of Mosul that contained a shrine believed to be the tomb of Jonah -- who is revered as a prophet by Christians, Jews, and Muslims. The paper reported that the militants had wired the periphery of the mosque with explosives and then detonated them.

"They turned it to sand, along with all other tombs and shrines," Omar Ibrahim, a Mosul dentist, told The Journal. "But Prophet Younes [the Muslim name for Jonah] is something different. It was a symbol of Mosul ... We cried for it with our blood."

Religious officials in Mosul, as well as at Iraq's tourism ministry confirmed to The Journal that the shrine had been destroyed.

According to the hard-line Sunni ideology followed by ISIS and other extremist groups, veneration of shrines or tombs is a sin, as is the veneration of any prophet apart from Muhammad.

Officials told The Journal that ISIS militants had destroyed at least 24 shrines in Mosul alone. That number does not include Shiite places of worship or the Mosul Museum, which officials said was raided by militants this week.

Last week, thousands of Christians fled Mosul after ISIS issued an ultimatum requiring that Christians convert to Islam, pay a tax historically known as a "jizya," or face execution. The city had 60,000 Christians at the time of the U.S.-led invasion in 2003, and the Christian population still numbered 35,000 last month.

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