San Francisco, Jun 20 (IANS): The fast-growing Sites wildfire in Northern California remained just 5 per cent contained, officials said.

The Sites Fire, about 100 miles northwest of Sacramento, the capital city of the western US state of California, broke out on Monday and is among over a dozen wildfires that have ripped through the state, Xinhua news agency reported.

The blaze, currently the largest and fastest-growing wildfire in Northern California, has engulfed some 15,656 acres in Colusa County. Evacuations are ongoing, according to the California Department of Forestry and Fire Protection.

In Sonoma County, the Point Fire, which erupted Sunday in Geyserville and has burned more than 1,207 acres, was 50 per cent contained as of Tuesday evening.

In Calaveras County, a blaze that erupted on Monday afternoon has been dubbed the Aero Fire, and it has been deemed a threat to more than 3,600 structures. It was 33 per cent contained on Wednesday afternoon, having charred more than 5,351 acres.

Officials warned that the risk of new fires erupting in Northern California remained high.

The probability of ignition is "still up at around 100 per cent," said fire behaviour analyst Jonathan Pangborn of the California Department of Forestry and Fire Protection.