DETROIT, Mich.-- A 10-year-old Michigan girl is in critical condition after being attacked by a dog.

Detroit police say the girl was playing in a backyard when the dog left the house and attacked her.

Chief James Craig says the owners of the dog knew it was vicious and kept the dog locked in a room when strangers were present.

The girl's aunt tried to intervene, but ended up injured as well.

Police say a neighbor came over with a shovel and beat the dog to stop the attacks. 

The police chief says this is not the first time the dog had gone after someone.

Craig said the girl suffered serious injuries to her arms and legs. The aunt is also being treated.