A man deemed mentally ill was taken into custody Tuesday after bragging falsely that he was involved in the fatal shootings of two young girls on a rural country road.

The arrest briefly brought hope in a case that's puzzled investigators, who have struggled for more than a week to determine a motive while still waiting for the subject of a "person of interest" sketch to come forward with information on the killings.

Click here for photos.

Click here for a video report.

Investigators determined through extensive questioning that Weleetka resident Russell Neiley was not actually involved in the shooting. After being held on an emergency detention order, Neiley was taken to a mental health facility.

"It happened at the wrong time," Okfuskee County Undersheriff Darrell Summers said. "It's totally unrelated."

Police received a call Tuesday morning reporting a domestic disturbance at a Weleetka school, where Neiley was apparently dropping off one of his daughters.

"He was upset and said he was going to kill himself," Summers said.

Police followed him, then pulled his pickup over near the town of Henryetta and found a bolt-action rifle inside, Oklahoma Highway Patrol Lt. George Brown said.

The man threatened troopers that he was involved in the shooting deaths of 13-year-old Taylor Paschal-Placker and 11-year-old Skyla Whitaker, whose bodies were discovered June 8 along a back country road near Weleetka.

"We [had] a guy in custody, but it has nothing to do with the case," said Rex Hefner, Okfuskee County jail administrator.

Since Friday, the day when the girls' funerals were held, authorities have been searching for a "person of interest" they want to interview about the slayings.

The man in a sketch released by the OSBI is described as an American Indian, about 6 feet tall, with black hair and a ponytail stretching to the small of his back. Investigators say the man was seen standing near a white Ford or Chevrolet single cab pickup with chrome striping and an Oklahoma license tag around the time and place the girls were shot.

OSBI officials said Tuesday they are pursuing up to 40 tips related to the sketch that had been called in from across the country.

"We're running down the same leads," said OSBI Special Agent Ben Rosser.

The girls were shot a number of times in the head and chest with weapons of two different calibers, leading authorities to think two gunmen were involved. Investigators also believe that bullet casings collected near the crime scene could be linked to the homicides.

More than $30,000 in reward money is available for information leading to an arrest and conviction.