An angry swarm of bees attacked construction workers in Riverside, Calif. on Monday after their hive was disturbed, killing one of the workers and injuring two others, according to authorities. 

The incident occurred at approximately 10 a.m. as the crew was grading the site for a parking lot when they hit an underground sprinkler vault the beehive was inside, according to Battalion Chief Tony Perna, Los Angeles Times reported.

Workers say the bees started swarming, causing them to panic and flee. Two of the construction workers covered their faces with their hands and rolled on the ground while the third worker tried to swat the bees using a vest, according to Fox News.

"It was insane," said fellow construction worker David Wold. "It all happened pretty quick, really. They just kept splitting up and chasing all the other workers," according to CBS Los Angeles.

One of the workers, who has not yet been identified, suffered an allergic reaction from the attack and succumbed to his injuries after being transported to a hospital in critical condition.