(Photo via CAIR.com)

The Arizona chapter of the Council on American-Islamic Relations Arizona called on state and federal authorities to investigate threats mailed to a number of Valley mosques as acts of domestic terrorism.

Two Valley mosques have reported receiving the same menacing letter, threatening Muslims with death.

On Sunday night, mosques in Phoenix and Tempe acknowledged receiving the anonymous letter. It includes several deadly threats and references a recent incident in Garland, Texas, when two Muslim extremists with ties to the Valley were killed there earlier this month after trying to attack a provocative cartoon contest.

Kristy Sabbah is with the Council on American-Islamic Relations Arizona. She said her group hopes the FBI will investigate the letter.

“We find that anti-Muslim extremists, like the ones that sent this letter, they have much more in common with the violent Muslim extremists than the vast majority of the Muslims do,” Sabbah said. “So both groups, they use threats of violence and alienate peace-loving Muslims and threaten houses of worship and religious leaders to further their political agendas.”

She said the national CAIR group is urging Muslim religious leaders who may receive similar warnings to take them seriously.

“We cannot any longer consider these empty threats, we have to protect the members of our community,” Sabbah said. “So that’s exactly what we’re doing. Any time we get anything going forward, we are definitely contacting authorities and asking FBI to investigate them as well.”

The state CAIR group recently received hate mail, though Sabbah believes it’s unrelated to the letter sent the mosques. She said the national group has noticed a recent increase in threats against Muslims all over the country.