Apparent partial human remains discovered Friday in the middle of a North Dakota farm field may be those of missing Vadnais Heights resident Michelle Newell, authorities said Monday.

The Cass County Sheriff's Office said the man last seen with Newell in August, Timothy J. Barr, provided information about the remains' location to Minnesota authorities on Friday.

Barr, 51, was charged Monday in Cass County with one count each of felony manslaughter and felony duty (to stop) in an accident involving death or injury. He is in custody in Minnesota awaiting an extradition hearing.

Hair, a forearm bone with the elbow connection, teeth and other small bones were recovered 5 to 10 feet away from a culvert in a farm field, according to authorities and charging documents.

"This [site] was on a minimum maintenance road, near the middle of a field," said the Cass County court documents. "Only someone with complete knowledge of where Ms. Newell was would be able to pinpoint where we found her."

Assistant Cass County State's Attorney Tristan Van de Streek said it's unclear what happened to the rest of the body.

"It would be hard for me to differentiate, at this point, what a person may have done vs. what animals may have done in the last couple of months," he said.

The Cass County charging documents reference evidence from a Ramsey County case brought against Barr in September in which an informant told Ramsey County authorities that Barr said Newell stole a pound of methamphetamine from him. She hid it in the woods and then hid from Barr. He "accidentally" backed over and killed her as she hid under his car.

Ramsey County authorities had charged Barr with two counts of second-degree murder without intent and one count of criminal vehicular homicide in Newell's disappearance even though no remains had been discovered at the time. The charges were dropped in October after his attorney argued that local authorities had no body or evidence to back up their case.

"It's very important, in a homicide case, to be able to prove death," Van de Streek said. "The manner of death can also indicate who was responsible, or how it was done, and that kind of evidence can only be derived from the body, so it's very important to have that body."

According to the Cass County charging documents, a man in Wheatland, N.D., Dakota saw Newell and Barr on his property about 2 p.m. on Aug. 30.

The man asked Barr what they were doing, and Barr said they were looking for a place to have sex.

The next day, the Cass County Sheriff's Office and North Dakota Highway Patrol were called to respond to a man lying in a roadside ditch west of the Embden exit on Interstate 94.

They found Barr, who was alone. He said he was resting because his car had broken down a few miles away.

Van de Streek said that conversation occurred relatively close to where the remains were discovered Friday.

Court documents show that an acquaintance of Barr's contacted the Ramsey County Sheriff's Office on Thursday to indicate that he wanted to speak with them about Newell's disappearance and the location of her body. Barr spoke to them the next day, pointed to her location on a map and was booked into the Ramsey County jail that evening.

Ramsey County sheriff's spokesman, Sgt. John Eastham, and Cass County Sgt. Tim Briggeman said they don't know what motivated Barr to turn himself in.

A news release from the Cass County Sheriff's Office cautioned that, "At this time, it is not certain that the human remains located are those of Ms. Newell.

The discovered remains were sent to the medical examiner's office to assist in the identification process."

Briggeman said the remains were found in "an extremely remote area that definitely doesn't have a lot of vehicular traffic." Citing protection of the investigation's integrity, he declined to specify whether the remains were found on private or public land, and the conditions under which they were discovered.

The Ramsey County Sheriff's Office made a plea in mid-October for the public's help in finding Newell. They said at the time that she may have been buried under hay or grass in the corner of an abandoned barn or farm building.

It also is unclear if authorities had searched nearby during previous attempts to locate Newell.

"At this time, I'm not willing to discuss the exact setting where the remains were found," Briggeman said.

Newell's best friend, Tara Hughes, welcomed the news of the discovery.

"Hallelujah," Hughes said. "She needed to be home."

Family members reported Newell missing on Sept. 8, noting that they last had contact with her on Aug. 29.

Barr and Newell, who met through a mutual friend, were seen together on a Taco Bell surveillance video in Alexandria, Minn., on Aug. 29.

Authorities believe Newell initially left the Twin Cities willingly with Barr.

Chao Xiong • 612-270-4708

Twitter: @ChaoStrib