At least eight people were killed in a wildfire that raced through southern Australia on Tuesday, forcing terrified residents to leap into the sea to avoid the flames, emergency officials said.

The blaze on South Australia's Eyre Peninsula (search), about 250 miles west of Adelaide (search), was the worst of several wildfires reported around the state, where temperatures have topped 111 in recent days.

Residents of at least one township were forced to evacuate their homes and seek refuge on a beach to avoid the flames, State Emergency Services spokesman Stuart Macleod said.

"Some people had moved into the sea to escape the fire. Our people picked them up and brought them back to shore," Macleod said.

The peninsula fire was reported late Monday and contained by firefighters, but flared up again on Tuesday before blazing out of control, police spokeswoman Kylie Walsh said.

At least eight people have been killed, but the number was expected to rise as the fire continued to blaze out of control, police inspector Malcolm Schluter told Sky News.

It was not immediately clear what started the blaze. Firefighters said Tuesday's weather made it impossible to contain.

"There is no firefighting force in the world that can stop the fire in the conditions we experienced today," Country Fire Service spokesman Simon Vogel told the Ten television network.

Two other wildfires also forced the closure of several Adelaide highways on Tuesday.