With the search for an autistic Minnesota man entering its sixth day, Burnett County authorities say hundreds of volunteers continue to scour the area.

Sheriff Dean Rolan said Saturday searchers are combing dense woods and wetland areas about seven miles south of Grantsburg.

They're looking for 25-year-old Keith Kennedy of Shoreview, Minnesota. He vanished Sunday from a camp for developmentally disabled adults.

Kennedy only can speak four words. He also relies on anti-rejection drugs after having a kidney transplant in 1995. Officials are worried his kidneys could shut down if he misses too many doses.

The sheriff says Kennedy might be drawn to buildings or vehicles. He asks anyone who lives in a 20-mile radius to check their property.