UFO 'playing with' helicopter over Ireland

A video posted to YouTube shows a helicopter dodging an erratically flying UFO over the skies of Ireland. What is it? The video is shot from a backyard garden and the sounds of the helicopter's blades can be plainly heard, although the chopper itself is too far off to make out very well. That means the unidentified flying object nearby is also too far away to make out clearly. But it's the way the object moves through the air which is mystifying. The helicopter is clearly moving toward it and hovers for a closer look. What happens next in the one minute video is where it gets weird. The UFO circles and spins faster than any known aircraft and seems to be playing a game of tag with the chopper. If this object were any usual aircraft, what it's doing would be extremely dangerous and illegal. The truly astounding aspect of this sighting is the crazy way this unknown craft is behaving with a helicopter so nearby.(SOTT)