A brother and sister have died after being pulled from the water in Port Burwell, south of London.

The siblings, a seven-year-old boy and a 10-year-old girl, were taken to hospital in London, where they succumbed to their injuries.

A teenager who was with them in the water was rescued.

OPP West Region Sgt. Dave Rektor said that the incident occurred at the main beach of the provincial park around 4 p.m.

The beach was crowded on a hot, sunny day, Const. Aaron McPhail said.

Laura Stypa, 19, said her parents were on a raft in the water when a young girl flagged them down, screaming that her brother was drowning.

“My stepdad found him facedown in the water, grabbed him and did CPR,” Stypa told CTVNews.ca. “The boy was throwing up.”

Several beach-goers then set out to find a second child in the water, forming a human chain out of fear that a strong undercurrent would sweep someone away, Stypa said.

Once the girl was pulled from the water, both children were rushed to hospital.

They were identified as being from Glen Meyer, in Norfolk County. The names of the children have not been released.

OPP are investigating.