A 22-year-old woman was seriously injured at China Walls in the Portlock area of Hawaii Kai Monday afternoon.

An Emergency Medical Services report said bystanders pulled the woman out of the water after apparently being dragged across the rocky ledge at China Walls at about 1 p.m.

The woman was a visitor who probably jumped off, “hit her head and swallowed some water,” said Shayne Enright, spokeswoman for the city Emergency Services Department.

“Thankfully there were other people there to help her get out of the water,” she said, but added that other people’s safety could have been jeopardized.

EMS said Ocean Safety personnel began treating the woman, who suffered a head injury, until firefighters and EMS personnel arrived.

EMS personnel took over treatment before transporting her to a trauma center in serious condition.

Enright emphasized that China Walls is a dangerous area.