The death of a 4-year-old Iroquois Point boy found in the trunk of a relative's car in July after a frantic search has been ruled an accident.

The city medical examiner's office said yesterday that Brayden Mara-Villegas died from hyperthermia "due to being confined in a trunk."

The cause of death had been deferred as the medical examiner's office awaited the results of toxicology results, which came back negative.

Brayden was found in the trunk of a relative's car on Ibis Avenue about 2 p.m. on July 18 after going missing while his mother was inside their home cleaning.

Police said when the boy's mother couldn't find Brayden, a relative went out to search the area.

The relative was driving a 1993 sedan and pulled over at one point when he saw a warning light on.

He then opened the car's trunk and found Brayden inside unconscious.

Firefighters said the boy had been in the trunk for up to an hour.

Experts have said temperatures in the trunk of the car could have exceeded 130 degrees. Brayden was taken to Hawai'i Medical Center West, where he died.

Police were investigating the death, and a spokeswoman could not immediately say yesterday whether the case would be closed given the medical examiner's ruling.

The death shocked the Iroquois Point community and left many wondering how the boy got into the trunk. Police have so far offered few details on the investigation.

Brayden was the fifth Hawai'i child to die from vehicular hyperthermia since 1997. The other four children were left unattended in hot vehicles.