The caretaker at a Philadelphia mosque said he found a severed pig's head outside on the sidewalk, and police were investigating whether someone may have thrown it out a car window.

The caretaker told police he found the head near the door of the Al Aqsa Islamic Society when he arrived around 6 a.m. Monday.

Police said surveillance video shows a red pickup slowing down in front of the mosque on Sunday night. The truck then circles the block and someone throws an object from the passenger window as it passes a second time.

The Quran, the holy book of Islam, prohibits Muslims from eating pork, and pigs have been used to taunt or offend Muslims. Last year, attackers in Greece placed a severed pig's head and painted anti-Muslim slogans outside an Islamic studies center in Athens.

The incident in Philadelphia was condemned by Mayor-elect Jim Kenney.

"The bigotry that desecrated Al-Aqsa mosque today has no place in Philadelphia. The City of Brotherly Love and Sisterly Affection has a long history of coming together in the face of challenge," Kenney said in a statement Monday night.

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