GREEN BAY, Wis. (AP) _ The death of a 12-year-old boy whose nude body was found in his family's portable dishwasher has been ruled accidental, authorities said Monday.

Brown County Coroner Genie Williams has not officially ruled on a cause of death, but Cmdr. David Zasada said initial indications are that Michael Conard ''very probably died of a lack of oxygen prior to the hot water'' beginning to circulate in the machine a week ago.

The boy, who was 4-foot-10 and weighed about 90 pounds, apparently used the soap dispenser inside the door to pull the door shut, Zasada said. There is no release mechanism inside the machine, he said.

The boy took off his clothes and watch before climbing in machine, apparently to see how it worked, Zasada said.

Suicide was ruled out because there was no note and friends, family and teachers indicated the boy was well-adjusted and happy, Zasada said.