A 49-year-old man slipped and fell into the Skykomish River Saturday afternoon, prompting a search team response that turned up unsuccessful.

Snohomish County Sheriff's Office responded to the scene near Index and Sunset Falls around 3:45 p.m. Saturday. The swift water rescue team, along with a search helicopter and volunteers, assisted with the search.

The man was hiking with a woman who called authorities when he slipped and fell.

The search area is 28 feet deep with a high volume of water going over the falls, Sgt. Scot Fenter said in a news release, "making it extremely unsafe and dangerous to deploy divers into the water."

Deputies used a remote underwater sonar and camera to search from the top of the water. The search lasted more than two hours.

The sheriff's office plans to resume the search when new information about the victim's location becomes available.