A mysterious drone flying over Pennsylvania spooked residents.

Footage filmed by resident Robert L Kline Jr shows an unmanned aerial vehicle with bright flashing lights in the skies over York County.

Robert said: 'This is the biggest of these so-called 'drones' I have seen. I would say it was maybe 200ft up and the size of a bus.

He also described its strange behaviour, noting that it seemed to interact with children, blinking faster as if responding to their excitement.

He added: 'It also made absolutely no sound at all until it was going away.

'I'm positive these are not drones at least not in the same sense as drones we are used to seeing. These are much more sophisticated to say the least.'

The sightings follow weeks of reports across New Jersey and other states since mid-November of dozens of bizarre drones spotted in the sky.

Flights near sensitive areas, including Picatinny Arsenal and President-elect Donald Trump's Bedminster golf course, led to temporary FAA flight restrictions.

Homeland Security Secretary Alejandro Mayorkas confirmed the sightings included drones and manned aircraft but assured the public there was 'no evidence of foreign involvement or threat'.

Officials said they remain alert but some lawmakers have criticised the government's slow response and lack of transparency.

Some have accused the government of covering up military surveillance or alien interference.