A fire has broken out at the border of Los Angeles and Ventura counties and is spreading rapidly, threatening numerous hillside homes in the Calabasas and Hidden Hills areas.

UPDATE Jan. 9, 8:35 p.m. The Kenneth Fire that erupted Thursday afternoon on the border between Los Angeles and Ventura counties is reportedly being investigated as an arson case, with one person in custody. As of Thursday evening, the blaze has expanded to 960 acres, with no containment.

Firefighters raced to contain a new wildfire that erupted near homes in the area of Calabasas and West Hills, northwest of Los Angeles, on Thursday afternoon. The Kenneth Fire has burned more than 900 acres and is 0% contained.

This article has been updated and a video removed to clarify there were no arson charges. LOS ANGELES (KTLA) – A man who was detained by citizens shortly after a wildfire exploded near Calabasas and West Hills is not accused of starting the fire,

A person of interest was taken into custody but had not been arrested as of Thursday evening. The alleged arson was reported about 5 and a half miles from the approximate start of the Kenneth fire, near Victory Boulevard west of Gilmore Street in West Hills.

Authorities said there was not enough probable cause to arrest the man on suspicion of arson, but he has been charged with a felony probation violation