Authorities have arrested a New York City man on charges he threatened to kill a director of a Muslim civil rights group.

Prosecutors say Bernhard Laufer sent threatening emails to a director of the Washington-based Council on American-Islamic Relations.

Laufer was expected to appear later Monday in federal court in Brooklyn.

A criminal complaint says Laufer wrote one email to the director that warned, "I am coming after you."

The 56-year-old Laufer was already facing attempted murder charges in a separate state case. The name of his attorney was not immediately available.