Evacuations were ordered in Riverside on Sunday afternoon after a vegetation fire quickly exploded to 63 acres, endangered homes and posed “an immediate threat to life,” fire officials announced.

Then, around 4:30 p.m., authorities said the fire’s forward progress was stopped.

A couple of hours later, the Mandalay fire was mapped at 83 acres.

The fire was reported around 2 p.m. in the area west of Tyler Street and Mandalay Court. The blaze swiftly jumped to 10 acres and then became a four-alarm fire, with firefighters requesting additional resources, including five engines, two hand crews, a helicopter and fixed-wing aircraft, according to Watch Duty, a nonprofit app that tracks wildfires.

Structures were reported threatened off Mandalay Court, Tyler Street, Jurupa Avenue and Gaylord Street.

Evacuations were underway along Mandalay Court, Eureka Drive and Gaylord.

Homeowners could be seen through the smoke-filled air watering their rooftops with garden hoses and packing their cars in video footage shot by OnScene.TV, a freelance news videographer.

A reception center was set up at La Sierra Senior Center, at 5215 La Sierra Ave.

At 4:07 p.m., a Watch Duty staffer reported that all fixed-wing aircraft were released, according to the incident command. But the firefighting continued and evacuations remained in place.

The cause of the fire was not immediately known.