PHILADELPHIA (AP) _ A woman who helped lead a highly publicized campaign to locate her missing daughter is being held without bail today on charges she killed the 17-year- old track star.

Vivien King, 42, was arrested Sunday on murder and weapons charges in the slaying of her daughter, Shilie Turner, who was shot six times, Police Commissioner Richard E. Neal said.

Police refused to discuss a possible motive or other details of King's arrest.

WPVI-TV reported Sunday night that police sources said King had confessed to the killing, saying she was drunk and high on cocaine the night her daughter came home late.

According to the report, the police sources said the mother and daughter had a troubled relationship, and coming home late was the last straw.

The Philadelphia Inquirer today reported that King told investigators, ''I was out of my mind. ... I'm sorry. I need help.''

Turner was last seen at 2:30 a.m. Jan. 18 after a bus dropped her off about six blocks from her home. Her mother reported her missing the next day.

Her frozen body was found Feb. 20 under some brush at a local park.

The girl had talked about wanting to leave home for two years because she didn't get along with her mother, her coach, Tim Hickey, said Sunday.

Local athletic officials had called Turner the best high school runner in the city and one of the five best in the nation.

She ran the anchor leg in several national championship relays, and three days before her disappearance she set a regional record for the 800 meters.

Her mother's arrest stunned teammates, friends and city officials who had joined Turner's family in a public appeal for information about the William Penn High School student's disappearance.

Hours before the body was found, King marched with about 150 others to call attention to Turner's disappearance.

''There's a lot of crying,'' said Donna Comrie, a friend of the victim. ''We're all just puzzled.''