Swarms of mayflies prompted officials to shut down Veterans Memorial Bridge in Pennsylvania for nearly an hour on Sunday evening, marking the second night in a row that the bridge was closed because of the bugs.

Authorities said that the swarm was so dense it led to motorcycle crashes. The mayflies swarmed the bridge's light and fell to the ground, which formed piles on the road.

Chief Chad Livelsberger, from the Wrightsville Fire Company, said that the flies have so far caused three motorcycle crashes, which could be attributed to poor visibility and the conditions brought about by the dead mayflies covering the roadway.

Livelsberger likened the phenomenon to a blizzard in June only that it was mayflies and not snow. The bridge spans the Susquehanna River and is about 28 miles southeast of Harrisburg, Pa., the state capital.

"It was very slick, almost like ice," Livelsberger said. "It was hard to stop, in the engine and the vehicles. ... When you go to pull out, all your tires would do was spin."

The swarms of flies prompted the closure of the Veterans Memorial Bridge late Saturday night. It was reopened early in the morning albeit authorities decided to shut it down again for 45 minutes past 10 in the evening on Sunday because of another swarm.

The workers who responded to the scene also had a hard time with the bugs because these flew into their eyes and mouths and even managed to get into their clothes and gears. Columbia Borough Fire Chief Scott Ryno said that they had to close their eyes and swat the bugs away because these were getting into their mouth.

Livelsberger also related that a swarm of mayflies flew into his car in the time it took him to open his vehicle's door and get inside. He added that they had to rip the radiators off to get rid of the bugs.

"This is the worst I ever saw it. I grew up in Wrightsville, my whole life, and we never had it that bad that it impinged driving abilities," Livelsberger said.

Livelsberger and his colleagues were at the scene for only about 20 minutes but even with that short period of time, their truck was caked with the bugs.

The Wrightsville Fire Company shared a video of them when they arrived at the scene but said that the clip cannot give justice to what it feels like being in the presence of millions of mayflies. Watch the video below:

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