Police say an 8-year-old Ossining boy somehow got trapped inside a mattress cover and suffocated over the weekend.

According to police, Deveion Ferguson was playing in his bedroom when he apparently zipped himself inside his mattress cover Sunday. The boy?s grandmother, Gail Brinkley, claims she went to her grandson?s room when she didn?t hear him playing. At that point, police say she discovered that Ferguson was not breathing. Brinkley cut open the mattress cover, tried to revive Ferguson and called 911.

Ferguson was pronounced dead on Tuesday night at the Westchester Medical Center.

Police say the mattress cover is the type used to control allergens and provide a barrier against the effects of dust mites. Ferguson suffered from asthma, according to police. Detectives at the scene found the cover turned inside out and the zipper apparently stuck.