On Wednesday, the Fresno Fire Department confirmed that a man was seen leaving the scene of the fires in a 'green or silver vehicle.'
Officials say the suspect is believed to have set five fires on Wednesday alone.
On May 20th, firefighters had asked for the public's help in identifying the suspect after he was seen driving away from a grass fire.
Investigators say the suspect is believed to have started three different fires last week.
"Just because it's a fire, doesn't mean it's a fire department problem," said Jay Tracy, the Deputy Fire Marshall with the Fresno Fire Department. "It's a City of Fresno problem."
Investigators believe the sole suspect is a man who drives a Lexus ES 300.
"It is registered in the Fresno area," said Tracy. "We believe it does have some identifiable markings that we will be interested in looking at further."
Surveillance video from a fire on May 20th off Bryan Avenue and Sussex Way in the West Central area shows suspect slowly driving down the street. He stops for a couple seconds, drops something from his car and drives off. Moments later you can see the flames that quickly spread into the nearby grass.
"If we're off fighting these small grass fires that are being intentionally set, that would detract from the firefighting forces that we have available to respond to these structure fires," said Tracy.
Investigators believe the man is also connected to a grass fire that broke out on Fruit and Dunn Ave in Southwest Fresno on Wednesday afternoon.
Firefighters said it torched about six acres.
"Fortunately we are able to save all structures," said Deputy Chief Jonathan Chew. "There were some fences that were burned, some vegetation but we able to make successful stops."
Leticia Solis' home is close to where the fire broke out. She said part of her fence was damaged but was worried it could have been much worse.
"I just came really fast outside," said Solis, "I come to my backyard and just turned the water hose."
"I just saw all the fire and grabbed all my kids and tried to be safe."
Authorities are also still working to identify a woman who is believed to have started four fires in northwest and southwest Fresno over the last five weeks.
Anyone with information about either suspect is asked to call the Fresno Fire Department at 559-621-2776.
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