Authorities in western Pennsylvania say the body of a missing 4-year-old boy has been found stuffed in a septic tank. A suspect is in custody.

State police in Beaver County said Wyatt Smitsky was last seen outside his family's Greene Township home shortly after 7:30 p.m. Friday.

Trooper Robert Lagoon says a septic tank on a neighboring property was drained Saturday and the boy's body was found. He says authorities "have a known suspect and anticipate filing charges."

Hundreds of emergency personnel and volunteers searched dense woods with the help of dogs for the body, who had a heart condition, until 3 a.m. and resumed the search at 10 a.m. Saturday.

Authorities had also been using ATVs and a helicopter with infrared sensors, and the FBI also assisted due to the age of the victim.