Farmers on an Italian island shared video of a massive swarm of millions of locusts that have descended on the area.

Coldiretti, Italy's farming association, said the grasshoppers are causing damage to crops and posing a danger to livestock near the city of Nuoro in Sardinia.

The U.N. Food and Agriculture Organization said the cause of the swarm is unclear.

Cordiretti officials theorized an unusually cool May could be to blame for the influx of insects. They said the sudden warming of temperatures this month may have caused eggs laid in the autumn to hatch all at once.

The farming association said it is looking into options to prevent similar swarms from occurring in the future.