A fire-fighting helicopter pilot was killed in a crash, and dozens of homes burned in California on Wednesday as hundreds of lightning-sparked blazes forced tens of thousands of people to flee their dwellings.

Nearly 11,000 lightning strikes were documented during a 72-hour stretch this week in the heaviest spate of thunderstorms to hit California in over a decade, igniting 367 individual fires. Almost two dozen of them have grown into major conflagrations, authorities said.

Multiple fires raced through northern California's drought-parched wine country, shutting down Interstate 80 at Fairfield, about 56 km south-west of Sacramento, as flames leapt across the highway, trapping motorists caught in a hectic evacuation.

Mandatory evacuation orders

Four residents whose communities were overrun by flames hours earlier in the same area suffered burns but survived, though the severity of their injuries was not immediately known, said Will Powers, a spokesman for the California Department of Forestry and Fire Protection (CalFire).

He said thousands of residents were under mandatory evacuation orders in four-county area stricken by a cluster of nine wind-driven fires collectively dubbed the LNU Complex, which were triggered by lightning on Monday.

In central California, a helicopter was on a water-dropping mission in Fresno County when the aircraft crashed, killing the pilot, a private contractor, CalFire said.

There were social media accounts of people trapped in the blaze, but CalFire's Powers said authorities had no reports of missing persons.

A Reuters reporter saw dozens of burned-out homesteads and houses in the Vacaville-Fairfield area, dead livestock among torched properties and some animals wandering loose.

The last time California experienced dry lightning storms of such devastating proportions was in 2008, said CalFire spokesman Scott Maclean.

comment COMMENT NOW