UPDATE (Tuesday, May 2): Opera Fire near Moreno Valley reaches 100 percent containment

A 1,350-acre fire that started in the Highgrove area Sunday afternoon, April 30, is burning on Box Springs Mountain overlooking Riverside.

The fire was threatening about 40 homes in the late evening, and was 25 percent contained. Cal Fire/Riverside County Fire Department did not specify where the homes were located.

Earlier, officials had said the blaze no longer posed a threat to structures and communications towers on the hill. The fire was one of three major blazes burning, with others in the Cajon Pass in San Bernardino County and south of Corona in Riverside County.

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The Highgrove-area blaze, dubbed the Opera fire, was reported at 3:43 p.m. in a field near East Palmyrita Avenue and Opera Loop. It moved quickly, pushed by moderate winds. It was reported 15 percent contained as the sun set.

No injuries or structure losses were reported, but shortly after 8 p.m. the blaze appeared to be threatening an industrial building south of Palmyrita Avenue, just west of Mount Vernon Avenue in northern Riverside.

The Opera fire threw a shroud of smoke over the shoulders of Box Springs Mountain that was visible throughout the area.

On the Moreno Valley side of the 3,081-foot elevation mountain, residents had plenty of smoke, but no fire.

Jedediah Brown, 82 of Riverside, just moved into his daughter’s home Friday on the upper portion of Pigeon Pass Road.

“I’m getting up there in age so my daughter asked me to live with her and her family,” he said. “This is not the welcome to the neighborhood gift I was expecting.”

John Alexander, a Highland resident, was watching with his wife, Kandi from the other side of the mountain. They had come to the area to see the fire, which was near John Alexander’s office and the church the Alexanders attend.

“We’re just thankful the church was saved.” he said.

Near the fire there were at least three engines at the end of Mount Vernon Avenue. Cars were lined up along Palmyrita Avenue and people were using smartphones to take photos and videos of the blaze.

The area along Palmyrita was lined with two-story industrial and office buildings. Flames on the hill could be seen from some places Palmyrita.

Firefighters from Cal Fire/Riverside County Fire Department and city of Riverside were battling the blaze, with fire equipment and spectators gathered at East Palmyrita Avenue and Mount Vernon Avenue.

Aerial firefighting was briefly grounded because of interference by civilian drones, Cal Fire Capt. Lucas Spellman said. Shortly after 7 p.m., firefighting helicopters appeared to be engaging the blaze.

This story is developing. Check back for more information.

Staffer Doug Saunders contributed to this story