A soldier who went missing for four days after a solo navigation exercise died from hyperthermia and dehydration, according to autopsy results released Wednesday.

The body of Sgt. Lawrence G. Sprader, 25, was found about 8:30 p.m. Tuesday in a brushy area on the Central Texas Army post's training ground, said Eddy Howton, Fort Hood's director of emergency services. He had been missing since Friday, prompting hundreds of troops to search for him for days amid 90-degree heat.

A brief report on the autopsy, conducted at the Southwestern Institute of Forensics Sciences at Dallas, was released by a Bell County justice of the peace. The report did not provide further details.

Sprader was last heard from when he was on a solo exercise to test basic map-reading and navigation skills at the sprawling central Texas post Friday evening, said Col. Diane Battaglia, a III Corps spokeswoman at Fort Hood.Officials have said Sprader had two canteens of water when he left and had ample access to creeks and other water sources on the training range.

The experienced soldier was found dead four days later..

Three thousand soldiers and searchers from 14 outside agencies spent four days covering 20,000 acres of terrain. They searched on foot, horseback, using ATVs, helicopters and a heat-detecting plane in sweltering weather before the body was found by Eddy Howton, Fort Hood's director of emergency services.

The body was then sent to Dallas Wednesday for an autopsy. Battaglia did not have information on whether his body was found within the boundaries of the land-navigation course.

Officials do not suspect foul play, said Lt. Col. Carter Oates, commander of the 11th MP Battalion, Criminal Investigations Division, where Sprader was assigned.

Sprader's body was found near plenty of drinking water from creeks and other sources, said Robert Volk, the chief game warden at Fort Hood, who helped in the search. He said there are predators such as poisonous snakes and mountain lions on the post.

Officials declined to answer questions about whether there were signs of distress that might indicate how Sprader died, saying all that is under investigation. Howton said he did not know if searchers found anything that would indicate how long Sprader had been dead.

"We are deeply saddened for his family," Howton said. The family did not attend a briefing Wednesday.

When commanders reached Sprader on his phone late Friday — the last time anyone spoke to him — he did not indicate he was ill or distressed. But searchers were worried he may have succumbed to the 90-plus degree heat. Sprader was equipped with two canteens, a water backpack and two Meals Ready To Eat.

Sprader was one of nearly 320 noncommissioned officers taking part in a two-week leadership course.

Nine other soldiers got lost during the three-hour exercise, but all except Sprader got back to the rally point safely by following the sound of a siren that blasts when time is up, said Col. Diane Battaglia, a III Corps spokeswoman at Fort Hood.

Post officials said no other soldier had ever been lost on the heavily used range long enough to prompt such a huge search.

Sprader had returned from an Iraq deployment in September and worked in the criminal investigation division of Fort Hood. The Prince George, Va., soldier had no orders for redeployment to the war zone.