A civil rights group is calling for greater police protection of mosques after several in California received letters that praised President-elect Donald Trump and threatened Muslim genocide.

The Council on American-Islamic Relations, or CAIR, said that the same letter was sent to multiple mosques last week according to the Los Angeles Times.

The Islamic Center of Long Beach, the Islamic Center of Claremont and the Evergreen Islamic Center in San Jose all received the latter that was addressed to “the children of Satan.” It was then signed by “American for A Better Way.”

“There’s a new sheriff in town — President Donald Trump. He’s going to cleanse America and make it shine again. And, he’s going to start with you Muslims,” the letter states, CAIR reported. “And, he’s going to do to you Muslims what Hitler did to the jews (sic).”

CAIR-LA’s executive director Hussam Ayloush said the “irresponsible, hateful rhetoric” of the Trump campaign has fueled “a level of vulgarity, vile hatred and anger among many self-proclaimed Trump supporters.”

“I’m not saying (Trump) created racist people,” Ayloush said. “He normalized it. While he might say he’s not responsible, and I respect that, I remind President-elect Trump that he has a responsibility to act as a president for all Americans.”

A spokesman for the San Jose Police Department said officials have opened an investigation in the incident.

The Associated Press contributed to this report.

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