"The officers returned fire, and the suspect was shot and killed," said Lamar Shoemaker, Brown County sheriff.
The deputy, Todd Widman 21, apparently was shot inside his car along U.S. Highway 36 about 7 p.m. Wednesday and radioed for help, Shoemaker said. He was found outside his car and later died at a hospital.
More than 50 officers from various area law enforcement agencies converged on the scene, responding to Widman's call. The boy, who was armed with his own handgun, was found at 9:10 p.m. near the parking lot of a Wal-Mart store, and fired several shots on officers before he bolted, Shoemaker said.
A half-hour later, the boy was spotted in a field and authorities cordoned off the area. He came out of the woods nearby and fired on three officers. Two of them fired back, killing him, about 9:45 p.m., Shoemaker said.
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The boy was believed to be in his mid-teens, but his identity was not known, Shoemaker said.
However, The Buffalo News in New York reported police were trying to verify if it the teen was the 16-year-old son of a Buffalo police lieutenant, reported missing Tuesday after he fled in the family's car, apparently distraught over bad grades.
The News reported that Kansas authorities contacted Buffalo police early today after learning the gun he was carrying was registered to his father.
"We're on the phone with New York authorities right now," said Scott Teeselink, a spokesman for the Kansas Bureau of Investigation. "I can't confirm it right now, but we're on the phone trying to confirm those things."
Widman, a recent high school graduate who was studying criminal justice at Washburn University, had responded to a call from a motorist Wednesday night who saw the teen walking along the highway in Hiawatha. The city is about 10 miles south of the Nebraska border and about 35 miles west of the Missouri state line.
The motorist apparently believed the boy was a runaway, Shoemaker said at a news conference.