Story highlights Suspect Quinton Laster makes his first appearance in court

Police found the 20-year-old grandson outside and his slain grandparents inside an Oklahoma home

3 children were inside a garage attached to the house, which doubled as a day care

(CNN) A 20-year-old man allegedly shot and decapitated his grandparents inside an Oklahoma City home that doubled as a day care.

Investigators who came to the house for a welfare check Tuesday afternoon found three children huddled inside an attached garage. The children were unharmed, police said.

But inside the house, authorities found a grisly scene. Sharon Reed, 59, and James Reed, 78, were dead.

"Both victims had been shot and decapitated," police said

Officers had spotted Quinton Laster, 20, outside. They detained him there as they ventured into the house. Now, police say Laster, the Reeds' grandson, is being held on two counts of first-degree murder.

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