A state trooper on routine patrol found the body of a missing 10-year-old girl in a stream Sunday morning, five days after she apparently accepted a ride from a young man in a truck while she returned home from running an errand.

The trooper found the body of Katlyn "Katie" Collman (search) in the stream in a wooded area about a quarter of a mile off Interstate 65 about five miles north of Seymour, Sgt. Jerry Goodin of the Indiana State Police (search) said at a news conference.

Goodin did not disclose how the Crothersville girl died or how long her body may have been in the stream. An autopsy was scheduled for Monday in Louisville, Ky.

"This is a saddening day for law enforcement officials," Goodin said. "We've come to know Katie. It hits everyone very hard."

The discovery of the body about 10 a.m. Sunday came three days after authorities issued an Amber Alert (search) for her and two days after her parents issued a public appeal for her safe return on Friday. Also on Friday, authorities released a sketch of a young man whom a witness said was driving a pickup truck Collman was seen in.

The sketch sparked a rash of telephone tips, but none that provided solid information.

A $10,000 reward for information in the case remains offered.

No family members spoke during the news conference Sunday afternoon at the Vernon Township Fire Department in Crothersville, which has served as the command post for agencies that mobilized to search for the girl. It was there that Collman's parents, Angie Collman and John Neace, issued a written statement Friday appealing for their daughter's safe return.

"Please do not harm her. We ask that you just drop her off anywhere so that she may return to a family and community that loves her very much and misses her dearly," the statement said.

Collman's family had last seen her about 4 p.m. Tuesday as she walked to a store about three blocks from her home to buy toilet paper, investigators said. A clerk told investigators that the girl bought the toilet paper, and an acquaintance talked to her about a block away as she headed home.

A witness who saw Collman in the truck said she looked like a normal passenger.

"There was no sign of her being held against her will or trying to get out," Goodin said at the time.

Goodin said authorities waited two days to issue an Amber Alert for Collman because they needed a lead in her disappearance. Alert criteria say authorities must have a lead on a missing child's whereabouts before an alert can be issued.

Once police received a description of a truck — a white Ford F-150 pickup truck about 15 years old that appeared to be clean and well-maintained — they issued the alert, Goodin said.

The sketch of the truck's driver shows a very thin white male, 5 feet, 8 inches to 6 feet tall, 18 and 20 years old with short, dark hair and a fair complexion. A description said the man smokes cigarettes.

Collman, a fourth-grader at Crothersville Elementary, "always had a smile on her face," said Terry Goodin, superintendent of the Crothersville schools.

Counselors would be available at Collman's school on Monday, said Terry Goodin, who's also a Democratic state representative and the brother of the state police sergeant.