Brent Hinds, former guitarist and vocalist with the Grammy-winning heavy metal band Mastodon, died in a motorcycle crash in Atlanta late Wednesday, police said, leaving bandmates in a state of "unfathomable sadness and grief." He was 51.

Mr. Hinds, 51, was found unresponsive late Wednesday after an S.U.V. appeared to slam into the motorcycle he was riding near downtown Atlanta, the authorities said.

"We are heartbroken, shocked and still trying to process the loss of this creative force," the band said in a statement.