LIVE OAK, Fla. — The front yard of the house off 173rd Place was full of toys Tuesday morning.

But they were accompanied by silence after an afternoon of playing turned into tragedy Sunday evening.

Three children — ages 1, 4 and 6 — were playing on a trampoline in the front yard of the mobile home off the dirt road just west of Live Oak around 5 p.m. Sunday when, for unknown reasons, they climbed inside a nearby chest freezer when the mother of one of the children went inside to use the restroom. The children got trapped inside and died.

SCSO, which has not released the names of the children or their relatives, is still conducting its investigation. Foul play is not suspected.

Sheriff Sam St. John said Tuesday morning that results of an autopsy showed the children suffocated to death but showed no other injuries.

“It’s just really, really heartbreaking,” St. John said. “I really believe it was an accident, just a really horrific, terrible accident.”

St. John said the mother of the 4-year-old girl came back outside 10 to 20 minutes later and couldn’t find the children. The 6-year-old boy and the 1-year-old girl were siblings.

The woman then awoke the grandmother of the other two children and they began searching the property and an adjacent vacant home, according to the sheriff’s office.

After searching for approximately 20-30 minutes, the women found the children inside the freezer and not breathing.

“Right next to the trampoline,” St. John said, noting it was maybe 10 feet away in the front yard.

The women began attempts to resuscitate the children while calling 911.

The 5 cubic foot freezer, which was not plugged in, had a hinged hasp installed on the lid in order to be padlocked.

Authorities believe that when the lid closed, the hasp fell shut and trapped the children inside.

When Suwannee County Fire Rescue and SCSO deputies arrived on scene, the women were still performing CPR on the children, who were then transported to an area hospital, the report states.

Resuscitation efforts were not successful.

“It took an extended amount of time to find them and by the time they did, it was too late,” St. John said.

St. John said the case will be discussed with the Third Circuit State Attorney’s Office on Wednesday. The Florida Department of Children and Families has also been notified.

Students in the oldest child’s class at Suwannee Primary School had the situation explained very carefully to them Monday by SPS Principal Marsha Tedder, Assistant Principal Lisa Garrison along with the school psychologist and counselor. They told the class that an accident occurred and the student passed away.

“Our prayers and thoughts are with the family,” Tedder said. “He is going to be missed.”

The students in the class drew pictures of their memories of the student and it has been combined into a memory book that will be presented to the student’s family.

“He was a very happy little boy, who loved school,” Tedder said. “He loved his teacher and it was evident his teacher loved him. His classmates adored him. We are going to miss him.”

SPS has offered grief counseling to the students, parents and staff. The school also sent home materials about understanding grief in young children.

“Our hearts and prayers go out to the family,” Superintendent Ted Roush said.