INDEX, Wash. (AP) — Officials are investigating after the bodies of two men were pulled from the Skykomish River in an apparent double drowning, officials said.

Rescue workers were called to Mount Index River Road in Snohomish County around 2:15 p.m. Saturday after the men were found in the river, Sky Island Fire Capt. Vargas said. The incident occurred at Cable Drop Trail near Sunset Falls, KOMO-TV reported.

Bystanders pulled the men out and began CPR, before medics took over, officials said. The victims, whose identities were pending, were pronounced dead at the scene. Investigators said they were both in their 50s with one victim from Seattle and the other from Kirkland.

Witnesses told authorities that no one saw the men in the river prior to seeing their bodies, and it was not immediately clear where they entered the river.

Authorities said it was not immediately known if the two were with anyone else although fire officials flew a drone over the scene to try and find other victims. The cause of death for both victims was under investigation.