WASHINGTON, Oct 1: Vandals attacked a mosque in Idaho following a series of threatening phone calls to the religious institution, the Council on American-Islamic Relations said on Tuesday.

A representative of the Islamic Center of Boise, Idaho, told the Islamic civil rights and advocacy group that vandals used a rock and a cinder block to break four windows in the center and to damage a computer printer.

The attack apparently occurred sometime between midnight and 6 a.m. on Monday and was noticed when worshippers came to the mosque.

Both the Boise Police Department and the FBI have been notified. The council and mosque officials have asked that the incident be investigated as a hate crime.

The mosque had reportedly been receiving harassing and threatening phone calls since the Sept 11 terrorist attacks last year.

The frequency of the calls increased around the one-year anniversary of the attacks, mosque officials said.

There are an estimated 5,000 Muslims in the Boise area.