California - A California couple didn't report that their 10-year-old daughter had been shot for more than five hours because they mistook her bleeding for a period, police said on Friday.

The girl was sleeping in her Hayward home on Thursday when a stray bullet from drive-by shooting wounded her in the buttocks, Sgt Mark Ormsby said.

When the girl woke up in pain and had blood in her underwear, her parents thought she had started her period, police said. They also found no indication she had been shot when they took her to the bathroom.

Ormsby said when she woke up for school and was still in pain, her parents inspected her bed and saw bullet holes.