In an embarrassing statement to a parliamentary sub committee this afternoon, RAF chief Sir Rostron Riddle-Me-Ree told ministers that last week, aliens probably had been hovering over London for half an hour, in giant spacecraft shaped like a cloud, before being detected by a local man.
The incident only came to light when Will Fitzgerald ,56, of Peckham, lost the kite he was flying from Rutsones Park.
"The giant intergalactic craft was cunningly shaped like a cumulonibmus cloud", Fitzgerald told the Medium Cheese.
"I was innocently flying my kite and then 'whoomph' a giant laser zapped out of the craft and incinerated it. A massive blue spark came down the strings and knocked me to the ground", he said.
Fitzgerald showed us burns on the palms of his hands. In spite of his injuries, he struggled to a phone box and dialled 999, and reported the matter to local police, who called in the RAF, who said the craft was completely invisible to their radar.
The government is now preparing for the iminent alien invasion by sending more soldiers to Afghanistan.