Arbaeen Wali shrine Photo Al-Sumaria News.

BAGHDAD — “Islamic State” militants controlling the Iraqi city of Tikrit blew up a Muslim shrine and rigged one of the region’s oldest churches with explosives, security sources and witnesses said Thursday.

A police lieutenant from the area around the city, which is controlled by the “Islamic State” group (IS), said Al-Arbain mosque was dynamited on Wednesday.

The shrine is the reputed burial site of 40 early Muslim figures, including companions of Prophet Mohammed.

IS considers worshipping at burial sites to be tantamount to idolatry and has blown up several revered shrines across Syria and Iraq.

Witnesses said that IS gunmen set up the explosives inside the shrine on Tuesday and detonated them the next day.

“Yes, they have blown up this holy site,” said Yahya al-Attawi, the imam of the main mosque in Tikrit, speaking from outside the city.

Elsewhere in the hometown of executed former president Saddam Hussein, IS also rigged the Green Church–a striking structure carved into the rock and first built in the seventh century–with explosives.

Residents said many streets, homes and public buildings had been booby-trapped by the extremists who have held the city for more than three months and fought off attempts by government forces to take it back.