TACOMA, Wash. -

An Amber Alert has been issued for a Western Washington teenager.

Tacoma police said Briana Troyer, 16, went missing Tuesday night. She is white with brown hair and blue eyes. She is 5 feet 2 inches tall and weights about 105 pounds. She was last seen wearing a Wilson High School bowling shirt, a Wilson sweatshirt and jeans.

Police said she is a special ed student and has a mental age of a 9-year-old.

Briana walked away from the Tower Bowling Lanes around 5:30 p.m. Tuesday with Terrence Powell, 19. Powell is a level one sex offender. He is a black man with brown eyes. He is about 5 foot 9 inches and 220 pounds with short dyed blond hair. He was last seen wearing all black clothes with a white do-rag.

Briana is the daughter of a Pierce County sheriff's detective.