(AP) — An armed man was fatally shot by deputies Monday at an east Tennessee high school after he went inside and pointed a gun at the principal’s head, a sheriff said.

“There’s no doubt in my mind he went there to kill someone today,” Sullivan County Sheriff Wayne Anderson said at a Monday afternoon news conference hours after the gunfire at Sullivan Central High School. “I don’t know who, and I don’t know why.”

WJHL-TV reported that Anderson said a Tennessee Bureau of Investigation will likely determine the motive.

No students or teachers were hurt and school was dismissed at 10:30 a.m. EDT.

Anderson said Thomas Richard Cowan, 62, of Kingsport confronted a security officer Monday morning after entering the school about 9 a.m.

Cowan entered the school with a .380-caliber semiautomatic and a .25-caliber handgun in his back pocket, Anderson said. The sheriff said that after Cowan grabbed the principal, Melanie Riden, and pointed the semiautomatic at her head, student resource officer Carolyn Gudger pulled her gun on Cowan and moved the principal to safety.

Anderson said Gudger moved Cowan down the hall and away from the cafeteria to a science pod. When Sullivan County deputies arrived, they ordered the gunman to drop his weapon, and he allegedly pointed it in their direction. He then pointed it back toward the school resource officer, prompting deputies to fire, Anderson said.

Blountville is near the Virginia line, about 250 miles east of Nashville.

___

Information from: WJHL-TV, http://www.wjhl.com/