[h=1]Farmers baaa-ffled after hundreds of sheep are branded with smiley face[/h] [h=3]A MYSTERIOUS smiley face has appeared stamped on the side of hundreds of sheep across the UK.[/h] The odd image was first spotted on 20 animals grazing in a field in Melton Mowbray, Leicestershire. There have since been sightings in a further five fields, from Perthshire in Scotland to Exeter, 500 miles away in Devon Photos of the sheep have gone viral on Twitter, with users sharing sightings and speculating about the source of the smiley face - using the hashtag #creepysheep. Pranksters are being blamed for the bizarre branding - but some internet users are convinced aliens are responsible. Farmers, meanwhile, are scratching their heads - wondering why their flocks have been targeted. Flocking hell ... Twitter users have shared photos of the sheep and speculated about the source of the smiley faces Ros Turner, whose sheep have been ’tagged’ in Melton Mowbray, said: “Passing motorists and walkers have had to double take. "They can’t quite believe what they are seeing and I’ve had a few people stop me and ask what is going on. "It’s like crop circles - but on sheep. "The animals do not seem to have been affected in any way. They are still grazing and going about their day to day lives in the usual way." And Ellie Stokeld, another affected farmer, from Great Ayton, near Middlesbrough, said: “The symbol looks bizarre but it makes a nice change to the sheeps’ usual plain white coats. “You can’t help but laugh when you see the sheep in the field with the smiley faces on the side."