Ocean County Sheriff Michael Mastronardy said his force launched its drone after one of his officers saw 50 unmanned aerial vehicles, 'coming off the ocean'.

The maritime agency then reported seeing spotted 13 drones following their boat, estimating that the devices had a wingspan of eight feet.

Matronardy said the force put up an 'industrial grade' drone to follow one of the devices, but it quickly slipped through their grasp.