An 8-year-old Columbia girl and her father were treated for lacerations after the family pit bull attacked the girl and the father tried to help her, police said.

Naihl Johnson was playing with the dog about 8:35 a.m. Sunday in her bedroom in the 7100 block of Natures Road when it turned violent and clamped down on her arm, tearing the skin, said Pfc. Denise Walk, a police spokeswoman.

She broke free and ran, but the dog gave chase and attacked her again, this time grabbing her wrist. Officials said Willie Johnson, Naihl's father, tried to pry the dog off his daughter - cutting his fingers on the animal's teeth - but could not, so a family member got a knife from the kitchen and stabbed the dog until it released its grip.

The girl was treated and released from the Johns Hopkins Children's Center. Her father was treated at Howard County General Hospital.

The injured dog was destroyed by Animal Control.