May 16 (UPI) -- Mandatory evacuations have been ordered for residents near Topanga Canyon in LA County where the Palisades Fire, which nearly doubled in size over Sunday, is being investigated for a "suspicious start."
The LA County Fire Department said the Palisades Fire, which ignited Friday just west of Los Angeles, had scorched 750 acres by Saturday evening. By Sunday afternoon, it had grown to 1,325 acres with zero percent contained.
Fire officials said weather conditions early Sunday were "favorable" but turned later in the day as temperatures rose causing "flare-ups" toward the fire's edge.
"[LA County Fire Air Ops] water dropping helicopters & ground personnel continue the fight in steep, rugged terrain," it said via Twitter.
The area of "very dry" brush and vegetation hasn't burned in more than 50 years, the department said.
The fire has prompted authorities to issue mandatory evacuations for two zones in the area: Zone 4, which consists of residents living east of Topanga Canyon between the Community House and View Ridge; and Zone 6, which runs north of Entrada, south of Oakwood and east of Henry Ridge.
The Department said some 1,000 people were affected by the orders.
No injuries have been report and the fire's cause remains under investigation, the department said.
Authorities have detained two people, one of whom remained in custody as of 6 p.m. Sunday and was being questioned by LA Fire Department arson investigators, the department said in a statement.
Authorities had earlier said the fire has been "deemed to be a 'suspicious start.'"
The department responded to a report of a fire in the Pacific Palisades at 10 p.m. Friday, locating the blaze in a steep canyon, prompting an air battle to ensure. By Saturday morning, it had grown to about 15 acres.