What caused the mysterious bright blue light over Peterborough last night

Residents across the city contacted the Peterborough Telegraph after spotting a moving bright blue glare in the sky last night around 10pm.

The light could be seen in both Bretton and Woodston.

Some residents speculated whether the bright blue light could be a UFO or a rare blue aurora. Others thought it could be a laser show or a helicopter. 
Peterborough Telegraph reader, Gintare Každailytė who lives in Bretton saw the strange glare at 10.10pm on Monday evening but ‘didn’t have a clue’ what it was.

The most likely explanation of the mysterious blue light came from Network Rail.

In a number of other cities blue lights had been seen and Network Rail had said in those areas that it had been caused by a special test train.

The test trains are used to identify faults on the lines with lasers that beam from the train.

The Peterborough Telegraph has contacted Network Rail for further comment.