The suspect has torched at least four laundry rooms inside a Central Fresno apartment.
At Hunter Place apartments, neighbors are fixating on unfamiliar faces, looking for the man caught in a surveillance video that recorded the man.
Jazmine Zamora is feeling uneasy because she lives above a laundry room.
In the last few weeks, an arsonist has set four different units on fire inside her apartment complex.
Fire investigators have no idea why.
"That's really scary. It makes me want to go sleep somewhere else until they find somebody because I don't want to wake up to a fire," Zamora says. "Maybe next time he can aim at my apartment, get tired of this apartment complex - do something bigger."
Through videos, firefighters are confident it's the same man in all four cases.
You can see him lighting small twigs or paper on fire before tossing them into a dryer and letting it burn.
"We're concerned that the little fires will turn into bigger fires. We've been lucky that the fires haven't gotten out of control," says fire investigator Jay Tracy.
Tracy, who works for the Fresno Fire Department, is concerned the arsonist could soon pick bigger targets.
Neighbors are too.
Investigators have been working with management to see if the suspect lives in the complex.
They say it doesn't appear he is on a lease.
It's why they're relying on the surveillance video to bring in more clues.