OMAHA, Neb. (AP) — The Islamic Center of Omaha has again been targeted — this time in a threatening email — and a Muslim civil rights group is asking officials to investigate the matter as a hate crime.

The Council on American-Islamic Relations has asked the FBI and local police to treat the email as a hate crime. The email, sent the day after Tuesday’s deadly attacks in Brussels, reads, “Your so-called peaceful religion just killed more innocent people. We think it is now time to fight back starting with you. Believe it. See you in hell.”

Mohammed Rasheed, a spokesman for the Omaha center, said he and other center members are concerned about the threat.

The center has been the target of vandalism in the last year.