IT was a sighting that alerted UFO spotters across the globe.

Caught on amateur video camera, six mysterious objects flew at incredible speed in formation across the skies above Manchester.

Excited cameraman Steve Harrison posted a message on etcontact.net, a website devoted to gathering evidence of UFOs worldwide and waited to learn if he had witnessed an alien flypast.

But the truth was arguably even stranger. Mr Harrison had witnessed a rare outing by another elusive phenomenon - the Dutch air force.

The mystery began when civil servant Mr Harrison, 51, was in his garden at Rossendale with his wife on Monday. Both of them saw six distinctive vapour trails appear on the western horizon.

In his report on etcontact.net, he said the objects were flying: "in a sort of formation i.e. not in a line."

Mr Harrison added that the objects were "travelling fast in parallel and in a pattern that was maintained from horizon to horizon.

"I videoed whole event and have perfect pictures of the trails, but despite zooming in I was unable to observe any craft or object at head of vapour trail."

He ended the report by speculating that the objects in the "amazing sighting" may have been meteors.

Investigators set about tackling the riddle and discovered the mysterious aircraft were actually F-16 fighter jets of the Royal Netherlands Air Force.

Although Holland is not renowned for its military might, the country was taking part in a massive Nato exercise - Operation Clean Hunter - across Europe and the UK.

Conducted from a base in Germany, the exercise involves planes attempting to take and defend air space.

Flights are conducted during the day to minimise noise and cover an area which extends from mid-France to Denmark and from the United Kingdom to mid-Poland.

Mr Harrison, who says he is "neither a sceptic nor believer" in UFOs, was disappointed to learn the truth.

"I thought they might be planes, but I couldn't see anything at the head of the trails and I didn't think they flew in formation at that altitude," he said.

"I thought it would be something much more unusual than the Dutch air force."

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