ADRIAN, Mich. -

The father of three missing Michigan boys from Morenci has pleaded no contest to three charges of unlawful imprisonment.

John Skelton entered the plea Thursday morning in Lenawee County Circuit court.

The brothers, 9-year-old Andrew, 7-year-old Alexander and 5-year-old Tanner Skelton, have been missing since Thanksgiving, when their father didn't return them to their mother, Tanya, after a scheduled visit.

Hundreds of people have searched woods and waters in Ohio and Michigan for the boys.

The case turned into a homicide investigation in February.

Skelton has said he gave them away to an organization, of which police said they have been unable to find.