GALLUP, NM — Relatives drove around their neighborhood for up to an hour searching for four young cousins before discovering they were locked in the trunk of the car, suffocating and dying from the heat.

The 13-year-old aunt popped the trunk after hearing a gasp while sitting in the car listening to the radio.

Two boys, ages 3 and 4, and a 2-year-old girl were pronounced dead Monday night after being pulled from the trunk. A 6-year-old girl died yesterday afternoon of heat stroke.

Police were treating the case as an accident.

The children apparently climbed into the trunk to play after Manuel Rohan, 24, the father of two of the children, left it open after removing a dead car battery he was going to charge, Lt. Craig Meo said. Police believe the children closed the trunk themselves.

About 20 minutes passed before the relatives noticed the children were missing and got in a car to search for them in nearby parks and playgrounds.

They drove for up to an hour before the children's 13-year-old aunt finally found them. She popped the trunk after hearing a gasp while she sat in the car listening to the radio, Meo said.

The car's trunk had weather stripping and may have been nearly airtight, Meo said. Temperatures outside were in the low 90s. Autopsies were planned, but he attributed the children's deaths to heat and asphyxiation.

Neighbor Melody Montoya, 17, said she watched as the family pulled the children from the trunk. "They were all blue and the oldest little girl was vomiting and trying to breathe and the dad was trying to help the little boy, giving him mouth-to-mouth, but he was gone," she said. "The mom had come home and I heard her scream and say that 'My kids are dead!' and she was screaming."

The children were Brianna Rohan, 2, Steven Dawson, 5, Ramon Torres, 3, and Christina Rohan, 6.

SALT LAKE CITY, UT — Five girls aged 2 to 6 were found dead Friday, dressed in bathing suits and locked in the trunk of an automobile, apparently the accidental victims of heat stroke, police said.

"Clearly the cause of death is heat exposure," Lt. Charles Illsley of the West Valley City police told reporters at the scene. "This is a horrible, horrible tragedy."

West Valley City is a suburb west of Salt Lake City. Temperatures in the area Friday were well above 90 degrees Fahrenheit.

"They were in there at least 45 minutes to an hour and probably longer," Illsley said.

"She said she was looking for her two kids. It seems like she was driving the car in which the children were in."

Two of the dead girls were sisters, and two others were their cousins. A fifth child from the neighborhood had been playing with them. The mother of the sisters had been baby-sitting the other children.

Police said they had been called by the woman when she could not find the little girls, who were wearing bathing suits because of the heat and had last been seen playing on the front lawn.

Before any officers arrived, she started her own search.

A neighbor told local television: "She said she was looking for her two kids. It seems like she was driving the car in which the children were in."

"We conducted a search for 45 minutes to one hour, neighborhoodwide," Illsley said.

The girls' bodies were finally found in the trunk of a Saturn sedan parked in front of the woman's ranch house in the middle-class neighborhood.

"The mother was too hysterical to tell us what happened or what the children were doing before it happened," Illsley said, but police were treating the deaths as accidental.

They said two of the dead girls were 6 years old, and the others were aged 2, 3 and 5.

Illsley said that although all the parents concerned had been notified, names of the victims would not be released for at least a day to allow distant relatives to be informed.

An official of the Mormon Church and a Roman Catholic priest joined the bereaved families as stunned neighbors gathered in front of the house.

"This is the refrigerator threat of the '90s," Illsley said. "We all know how refrigerators in the past were left out, and children would crawl into them.

"Nowadays a small child can climb into a late-model car, press a release button and open the trunk. A child very easily could have gotten into the trunk and somehow had the latch lock on them."

The case paralleled one in Gallup, New Mexico, in mid-July. Four children died after accidentally locking themselves in a car trunk in 98 degree heat, and relatives drove the car around for about an hour looking for them.