The president of the Colorado Muslim Society said the mosque on Parker Road received a threatening phone call Wednesday from a man who was upset about the death of 26-year-old Nicholas Berg, an American civilian working in Iraq.

The caller reportedly said Islam was a barbaric religion and that Muslims shouldn't be in the United States.

The society president said the mosque has received such calls periodically since the 2001 terrorist attacks.

The mosque has also received bomb threats, and authorities have been keeping a close eye on the building.

A video posted on a Web site linked to al-Qaida showed Berg beheaded by a group that said it was to avenge the abuse of Iraqi prisoners by American soldiers.