A 7-year-old girl was shot in the arm at a day-care center Tuesday after an 8-year-old classmate brought in one of his father's guns and it accidentally went off, authorities said.

The father was arrested for gun offenses, and court documents outlined an extensive criminal record. The boy also was charged, but authorities said that was done only so he could be helped by juvenile authorities.

The boy had the weapon in a backpack and was playing with it when it went off, said Montgomery County police spokesman Derek Baliles.

The girl was taken to a Washington hospital with a wound that was not considered life-threatening.

There were six children at the For Kids We Care Inc. daycare center at the time of the shooting, authorities said. Police said the boy had found the gun, a .38-caliber Taurus revolver, in a container in his father's closet.

Police charged John Linwood Hall Sr., 56, with leaving a firearm in a location accessible by an unsupervised minor, contributing to the delinquency of a minor, and possession of a firearm by a felon.

Montgomery County State's Attorney Douglas Gansler declined to give any details of the charges against the boy because of his age. The boy was to have his case reviewed by the Department of Juvenile Services, according to a police news release.

Neither youngster's name was released.

Hall has an extensive criminal record dating to the 1960s, according to court documents. It includes several convictions of assault with intent to maim and gun charges. He could be sentenced to five years in prison if convicted of being a felon in possession of a handgun and three years on the delinquency of a minor charge, authorities said.

The documents said there were "numerous" other weapons in Hall's apartment that his son had access to. Hall was in custody and could not immediately be reached for comment.

Gansler said the boy knowingly brought the gun to the day-care center and that the charges filed against him were in the "best interest of the 8-year-old to make sure he gets the help he needs" from the state.