Firefighters halted the progress of a brush fire blazing south of Diamond Valley Lake in Winchester that erupted Thursday afternoon.

The blaze scorched 1,261 acres, destroyed an unocuppied structure and prompted evacuations for six homes.

The non-injury blaze was reported at 2:20 p.m. in the 34000 block of Rawson Road, near Patterson Street. Te Riverside County Fire Department sent close to 100 personnel, who encountered fast-moving flames amid light to moderate winds, a spokeswoman said.

By 11:30 p.m., the fire was 40 percent contained and all evacuations were lifted.

Firefighters from the Riverside and Hemet fire departments and the Murrieta Fire Protection District were requested to assist in battling the blaze, on which four Cal Fire air tankers and two water-dropping helicopters were making runs.

Winds were blowing 10 to 15 mph out of the west, with relative humidity below 40 percent, according to area weather reports.

There was no word on what triggered the blaze.