A father and son ended up in hospital after a spectacular wipeout with their speedboat Sunday on Lake Simcoe.

York Regional Police said the 32-year-old son was discharged from hospital Sunday night while the 64-year-old father was kept overnight for observation.

They had been out on the popular recreational lake in a 14-metre-long Nortec speedboat, which is capable of reaching speeds of up to 160 kilometres per hour.

Witnesses said the boat hit a rogue wave in Killarney Bay around 4:30 p.m., causing the boat to roll.

"The boat is like, cut in half," said Denise Carl as she videotaped the aftermath of the crash.

She told CTV Toronto on Monday that the face of the younger man was covered in blood.

"There was fibreglass, there was pieces of everything all over the water," Carl said.

"It was very scary. I've never seen anything like that in my life," said Steve Wellington, another witness. "I knew right away when I saw that splash that the boat had flipped, and my heart just started pounding for the people in that boat."

People in nearby boats rushed to the aid of the duo, who were reportedly wearing lifejackets. However, the older man reportedly didn't have a pulse.

Wellington said that one woman, reportedly a doctor, started pounding on the the older man's chest and giving him mouth-to-mouth resuscitation. That restored his pulse.

"Thank God for her, because if not for her, today would be a different day," said Allison Wellington, Steve's wife. "They'd be planning a funeral."

Afterwards, the nose of the boat could be seen sticking straight up.

Police are investigating the incident.

In a separate incident Sunday, a boat struck a Toronto woman as she swam in West Lake, which is about 50 kilometres south of Belleville

The 53-year-old was airlifted to a hospital in Kingston. No update on her condition is immediately available.

With a report from CTV Toronto's Janice Golding and files from The Canadian Press