FRESNO, Calif. (KSEE/KGPE) – Fire crews in Fresno were fighting a commercial building fire Tuesday morning. 

Officials say the fire started around 4:00 a.m. near Clark Street and Tyler Avenue in central Fresno. As crews were making access, the fire spread to the roof. 

Because of chemicals in the building, firefighters say they had to fight the flames from outside. 

The cause of the fire is under investigation.