Updated

Los Angeles County coroner's officials say a spider bite didn't kill a 13-year-old Pomona boy who died mysteriously during the weekend.

The boy, whose name hasn't been released, died Sunday at a hospital after going into cardiac arrest. Pomona police say it was initially thought he might have suffered a spider bite a week or more before his death.

But coroner's Lt. Cheryl MacWillie says Tuesday that what had been thought to be a spider bite on the boy's body is a pimple.

She says there's no evidence that he was bitten by a spider.

An autopsy is planned Tuesday morning to determine the cause of his death.