UNIONVILLE, N.C. -- Propane tanks exploded during a fire late Monday night at the Southern Farm Equipment Store on Concord Highway in Unionville, which is north of Monroe.

The explosions spread the fire throughout the building. Paint products were also stored inside the store.

Firefighters said the building was engulfed in flames when they arrived on the scene. Four fire departments responded to the fire.

No one was hurt, authorities said.

Firefighters said they expected to be on the scene overnight because of hazardous materials at the site.