The superfast broadband has sparked controversy since rolling out this year, with health experts claiming it could have serious side effects on humans.
And there are now claims online that bees could also be affected after a video went viral.
I have proven that 5G kills vegetation, humans can get cancer. It is basically like sticking your head in a microwave. The amount of radiation is death threatening. Big Pharma doesn't care, as long as they can go forward with their project. Sometimes faster is not better.
The clip – taken in Sierra Madre, California - shows the lifeless bodies of the bees lying on the ground.
Philip Sites claimed they were spotted between two 5G poles – about 40ft apart.
“They have these things and they don’t even know if they’re safe for people,” he said in his video.
“But I can tell you they’re not safe for our environment because it is killing bees all over the place.”
He later claimed that “as I got further from the radius of the poles there were no more bees”.
More than 54,000 people have seen the clip since it was posted to YouTube on July 15.
Many viewers were horrified by the sight, with one saying: “Oh my God, thank you for documenting this.”
Another added: “That is not okay with me.”
But others questioned what was seen in the clip.
Some pointed out the bees could just be drone bees – which die after mating.
Others claimed the poles could not be holding 5G broadband, with one saying: “5G has only been installed in major cities, dude. It's not in Sierra Madre and it probably never will be.”
It is not the first time bees have been filmed dying on the floor under mysterious circumstances.