LOS ANGELES (CBSLA.com) — A civil liberties and advocacy group called for beefed up security Saturday at California mosques after it says an anti-Muslim letter was sent to two Islamic centers.

The Greater Los Angeles-area chapter of the Council on American-Islamic Relations (CAIR-LA) says the letter was sent to the Islamic Center of Long Beach and the Islamic Center of Claremont.

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CAIR-LA says the letter was addressed to “the children of Satan,” and went on to described Muslims as “vile and filthy people.”

The letter also went on to explain that President-elect Donald Trump was “going to cleanse America and make it shine again,” adding: “And, he’s going to start with you Muslims.”

Hussam Ayloush, the executive director of CAIR-LA, asked that the letter be investigated as an act of religious intimidation.

“Our state’s leaders should speak out against the growing anti-Muslim bigotry that leads to such incidents,” Ayloush said in a news release.

The organization says the same letter was sent to Evergreen Islamic Center in San Jose on Friday.

Police in Long Beach said they were going to be in contact with the Islamic Center of Long Beach to obtain more information.

KCAL9’s Jeff Nguyen spoke to local Muslims to show how they are dealing with the letters.

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“It’s kind of sad to see this kind of thing still exists,” said Nadya Aweinat.

She said it was hard to accept this letter in this day and age.

“That ignorance is shocked to me,” she said, “That there’s still that level of ignorance in our society.”

People in the mosque who have read the letter, postmarked from Santa Clarita with a fictitious name and phony address, said in addition to hate-filled it was rather juvenile.

“The handwriting is somewhat, no much of what they wrote, it’s someone that doesn’t have much intelligence. It’s written on a childish level,” said Regina Smadi.

CAIR says there has been an uptick in such incidents since the presidential election.

Aweinat says half her family isn’t Muslim but that the hateful words in the letter affected the non-Muslim side just as much.

She also said it’s beautiful to see how much support other churches and people of all faiths in the community have given the mosque.

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