DETROIT -

 A 14-year-old Detroit boy who stands accused of shooting his mother to death has been charged as an adult with first-degree murder.

Joshua Smith allegedly shot his mother, 36-year-old Tamiko Robinson, to death on Feb. 27 in her home on Burns Street.

Family members Local 4 spoke with said Robinson was sleeping on a couch at about 3 a.m. when she was shot by Smith, who used a gun the family had bought for protection.

Robinson’s fiancé, Chika Lewis, and her 5-year-old daughter were also in the house at the time of the shooting.

"I heard several gunshots, several," Lewis said.

He said he thought someone had broken into the house.

"Right, it turned out to be my step-son, killing his own mother," Lewis said. "It's cold-blooded. She didn't deserve that."

The teen was arrested by police a short time later after fleeing in his mother’s car.

Smith is also charged with felony firearm.