GOLDEN, Colo. - A Lakewood man has pleaded guilty to killing his girlfriend's 2-year-old daughter.

The Denver Post reports Keith Nick Ruiz acknowledged Friday he threw Dolci Gryshayeva to the floor and fell on top of her in the apartment he shared with his girlfriend. The toddler died Sept. 9, 2011, two days after Ruiz called 911 to report she had stopped breathing.

Dolci was taken to a hospital, where doctors found she had a severe head injury, bruises on her hip and chest and a 6-inch-long bruise across the middle of her back. She also had healing rib fractures and retinal bleeding.

Investigators say Ruiz told them he "snapped" because the child would not stop crying.

He faces up to 40 years in prison when he is sentenced Feb. 26.

In Nov. 2010, Daniel Aragon, who friends say was Dolci's father, fell to his death from a bridge onto a parking lot at what was then known as Invesco Field at Mile High.

Police said at the time that Aragon was wanted for a parole violation and had jumped from a moving car during a chase.