Investigators in southern California have questioned two people in connection with a wildfire that claimed the lives of four firefighters.
Officials in Riverside County questioned the pair Monday. No arrests were made.
Authorities said the fire was intentionally set last week. High winds fanned the blaze, which burned more than 16,000 hectares.
Four firefighters were killed when they were overtaken by a wall of fire driven by shifting winds. A fifth firefighter is hospitalized with serious burns over most of his body.
The fire has been fully contained.
A reward of more than $500,000 is being offered for information leading to the arrest and conviction of those responsible for setting the fire.
Some information for this report was provided by AP .