Detectives have closed the books on the 415-acre Calgrove fire without determining what caused it.

“The cause is undetermined and there will be no further investigation,” said Sgt. Craig Anderson of the Los Angeles County Sheriff’s Department Arson and Explosives Detail, adding that sheriff detectives worked with Los Angeles County Fire Department to determine the cause.

Many times, spot fires near freeways are caused by metal flying off of vehicles, causing sparks to land in brush, Anderson said.

The fire was initially reported near I-5 freeway and The Old Road, just south of Calgrove Boulevard on June 24.

About 1,000 people from 500 homes, including the Crescent Valley Mobile Home Estates, were evacuated Wednesday. More than 90 horses had to be evacuated from ranches in the area, as well.

About 415 acres burned with cleanup lasting for days, officials said.

“It was pretty hectic. We were just trying to get the horses out,” said Tanner Rodriguez, a horse owner. “You looked up and there were flames everywhere. We had to walk from Wildwood Equestrian Center all the way down (to Hart Park).”

“All animals were evacuated to Hart Park and transported to a private home on Bouquet Canyon Road and Vasquez Canyon Road,” said Santa Clarita Valley Sheriff’s Station Captain Roosevelt Johnson, in a press conference held Wednesday.

Some of the streets evacuated included Wildwood Canyon Drive, Champagne Lane, Green Crest Drive, Clearbank Lane, the SCV Senior Center on Market Street, Oak Bridge Lane, Davey Avenue, Eliott Lane, Roosevelt said.

The evacuations were lifted around 10 p.m. on June 24, about nine hours after the fire had began.

More than 450 firefighters and law enforcement officials from all over Southern California, including the Santa Clarita Valley Sheriff’s Station, Los Angeles County Fire Department, California Highway Patrol, Los Angeles city, U.S. Forest Service, CalFire, joined in the effort to battled the blaze.

A total of seven helicopters dropping water and four fixed-wing aircraft dropping fire retardant were on scene.

One structure was damaged by the blaze, said Los Angeles County Fire Department Deputy Chief John Tripp, in a press conference Wednesday, but it “appears the only damage is to the eaves of a garage.”

One firefighter fell and received burns from the fall. He was transported to Henry Mayo Newhall Hospital and then to a burn center, Tripp said.