– Through the long hours that thousands of searchers scoured fields and forests in blistering heat for a missing Wisconsin toddler, his body was in the trunk of a locked car that search teams passed by countless times.

On Thursday, Polk County officials were left trying to explain why the exhaustive search focused on acres of surrounding land and expressing regret that investigators hadn’t forced open the car’s trunk that held the body of 2-year-old Isaiah Theis.

The body was found about 10:15 p.m. Wednesday, a little over 24 hours after the boy disappeared while playing with his 7-year-old brother at the family’s home near Centuria, about 60 miles northeast of St. Paul.

The shocking discovery came when the car’s owner came to claim his vehicle from Justin Theis, Isaiah’s father, who works on cars near the family’s home, the Sheriff’s Office said.

Sheriff Peter Johnson said searchers had looked into the vehicle and in the area around it several times but hadn’t checked its trunk. They had been told that the vehicle had been locked before the boy wandered off and that it was “extremely unlikely that he could have been in it, based on that information,” Johnson said.

No word on cause of death

The search was instead focused away from the house.

Searchers had combed fields, forests, a pond and a swamp, because the boy’s family said he often wandered into the woods or up and down the road, Chief Deputy Steve Moe told reporters at a news conference.

It was presumed that Isaiah had wandered off once again, and that theory dominated the search process, he said.

In hindsight, Moe said, he wished that they had broken into the car’s trunk.

He said that deputies did not have access to the keys and that he wasn’t certain whether they were on the property.

“Would we liked to have forced entry to the car? Yeah, from my personal perspective,” Moe said.

He declined to speculate how Isaiah ended up in the trunk.

“I know that there’s strong interest in what caused it and what things led to the boy getting in that car,” he said. “It’s just too early.”

Johnson also said that “it would be inappropriate for anyone to speculate as to the cause and nature of [the] death until that examination has been done.”

An autopsy is pending.

Anguish among searchers

Isaiah’s mother told sheriff’s deputies that her son was last seen about 7:30 p.m. Tuesday while playing with his brother.

The boys’ family, friends and neighbors searched for him and then notified the Sheriff’s Office about 8:50 p.m. Tuesday when they couldn’t find him. That night, the Sheriff’s Office led a search of a 1-square-mile area around the house.

A Minnesota State Patrol helicopter equipped with an infrared device was called to help with the search, which was stopped at 1:30 a.m. Wednesday and which resumed again at daybreak.

More than 2,400 volunteer searchers poured into the area, pushing through the sweltering heat, methodically walking across acres of land, calling out Isaiah’s name. The Sheriff’s Office said that word about the missing boy on social media websites attracted many searchers.

On Thursday, Debbra White, 51, of Milltown, Wis., left a teddy bear and a wind chime at a makeshift memorial near a stop sign at 180th Street and 150th Avenue.

“There’s nothing I can say to bring their son back,” said White, who lost her 8-year-old son more than 20 years ago when he drowned in the St. Croix River.

She also left her contact information so that the family could reach out to her. Her 16-year-old son, Dalton, also wrote a note saying, “Sorry about your loss.”

Rachel Humpal, who owns a flower shop nearby, searched for Isaiah from 1 to 3 a.m. Wednesday, along with her husband and parents. She closed her flower shop early on Wednesday and rejoined her husband in the search.

“It still just baffles me. I’m sure we walked by that vehicle how many times,” she said Thursday. “That was one of my first questions — did somebody check the trunk?”

The manner in which the boy’s body was discovered left many of the volunteers who had searched heartbroken.

Melissa Johnson of Centuria joined the search at 8 a.m. Wednesday but was forced to leave at 2 p.m. because of the scorching heat. “I felt horrible. I wanted to keep looking, but I couldn’t,” she said.

“Then to find out that they found him in the trunk of a car … it hurts. … Why didn’t they open that trunk up and look?” she said. “I don’t understand it.”

On Thursday, she left an angel at the memorial site for Isaiah.

“At least we found him,” she said. “His family can have closure.”