The first fire broke out before 1:30 a.m. Friday in an abandoned building on Mariposa and G streets in Downtown Fresno.
Crews say the fire started inside the building and extended into the attic.
Due to safety concerns, they had to take on the blaze from the outside.
The fire did not extend to the building connected to it or any nearby buildings. The cause of this fire is under investigation.
Moments after the first fire, a two-alarm fire broke out in southeast Fresno.
This fire was reported before 2 a.m. Friday morning on Tulare and Jackson avenues, about two blocks from Roosevelt High School.
Firefighters received calls of people trapped in apartments due to a detached garage engulfed in flames.
They were able to contain the fire to the garage.
"It looks like the investigation led us to believe that a homeless man was in the alley and the fire got away from him," Fresno Fire Battalion Chief Tony Escobedo said "[it then] started the detached garage fire, and that destroyed the building."
A team was called in to knock down the building after it was declared a hazard.
No firefighters or residents were hurt and people were allowed to return to their apartments.
Firefighters remained at the scene Friday morning until the building was demolished.