Two vegetation fires were set within a 20-minute span Monday evening along Highways 180 and 99 in downtown Fresno, and Fresno fire officials are investigating whether they were intentionally set.
A third fire was set near California and Cedar avenues around the same time, but fire officials weren't sure whether it was related.
Later in the evening, a fourth vegetation fire was reported at Olive Avenue and Highway 41.
The fire fit into the "broader pattern" of recent fires, Battalion Chief Todd Tuggle said. He said the Fresno Police Department was questioning two possible suspects in connection with the fires.
A total of 14 units responded to the fires. No firefighters were injured, officials said.
Battalion Chief Tony Escobedo said Monday's fires were similar to another set of fires at Highways 41 and 180 on Sunday afternoon.
The nature of the spread of the fires, the multiple clusters and the timing lead firefighters to believe that the fires are possibly being intentionally set, Escobedo said.
The vegetation fires threatened structures along the freeways and one person was taken to the hospital to be treated for smoke inhalation.
Fresno recently has been hit with a spate of arson fires, and firefighters said they are investigating whether Monday night's fires are related to previous incidents.
Since May, Fresno has been hit by more than 20 arson fires. Fresno Fire Chief Kerri Donis said earlier this month that the city is almost certainly being targeted by several serial arsonists.
Tuggle asked anyone with information regarding the cause of Monday's fires to call the Fire Department at (559) 621-4000.
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