Police are investigating the mailing of a Quran submerged in a tub of what appeared to be pork lard to a Northern California Islamic center.

The Sacramento chapter of the Council on American-Islamic Relations received the package in June, and it follows two other incidents of defaced Qurans at nearby mosques last month. The Quran prohibits Muslims from eating pork.

Sacramento police are investigating the lard mailing as a "hate activity," but do not expect to file charges because the activity does not rise to a criminal level, Officer Linda Matthew said Friday. An incident rises to the level of a hate crime if it involved some type of illegal action, such as vandalism, Matthew said.

"It's deplorable behavior by someone to do something like this and it's very disrespectful to their religion, but yet there's no specific crime that's attached to it," she said. "We're monitoring these types of instances and taking them very seriously."

The package was sent from a shipping center in Houston by a white woman, but police do not know her name, Matthew said.

Police have notified terrorist threat assessment agencies in Sacramento and the Houston area about the incident, she said.

The incident is part of a larger trend in hate crimes and incidents happening across the county, said Katelyn Costa, the programs and administrative coordinator at the CAIR Sacramento chapter.

"We're more disappointed that people aren't taking the time to learn and understand," she said.

Two other incidents involving defaced Qurans were reported at nearby mosques last month. A singed Quran filled with bacon was reportedly handcuffed to a fence at the Masjid Annur Islamic Center in Sacramento. Also in June, someone reportedly threw pages torn from the Muslim holy book into the Islamic Center of Davis during evening prayer.

In April, 30-year-old Lauren Kirk-Coehlo was sentenced to five years of probation after she pleaded guilty to a felony hate crime for breaking windows at the Davis mosque and leaving strips of bacon on the handles at the entrance.