(FOX40.COM) -- A large swarm of bees attacked firefighters as they battled a grass fire Thursday, according to the Modesto Fire Department.

In the morning hours, Modesto firefighters who were stationed in Oakdale and Knights Ferry and CAL FIRE Tuolumne-Calaveras Unit were faced with what they called "an unexpected challenge" while trying to extinguish a fire on Sonora Road in eastern Stanislaus County.

On top of a blaze that consumed the grass, crews were met thousands of bees that complicated their firefighting efforts. The Modesto Bee reported that beekeepers were smoking bees in boxes to gather honey in the area near the fire.

Despite these obstacles, MFD said they maintained a swift and coordinated response and contained the fire to just 1.6 acres in under 15 minutes.