Story highlights Police found a burned Quran filled with bacon

A center has been targeted twice this year

(CNN) Two Islamic centers in Northern California were the sites of possible hate crimes during the last days of Ramadan, law enforcement officials said.

A burned Quran filled with bacon was found outside a Sacramento mosque Saturday, the Sacramento County Sheriff's Department said. It was hanging by a handcuff from a temporary fence outside the Masjid Annur Islamic Center.

"Sheriff's Hate Crime detectives were called to the scene to begin their investigation into the possible hate crime," the department said in a statement.

The center, which is the largest mosque in the greater Sacramento area, is next to a police station but it has been targeted in the past.

Another center was targeted about 20 miles west in Davis, California.

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