A recent surge in crop circles is being caused by drone users who upload their aerial footage on social media, a police force has said as it announced a crackdown on farm vandals.

Wiltshire Police issued the warning to the public yesterday following a spate of incidents in recent months, which officers said was being fuelled by scammers who generate publicity online in order to make money from advertising.

So far this year the force has been alerted to 16 incidents, with a recent circle in Alton Barnes measuring 200 acres in diameter. However, the true number is thought to be far higher because many farmers do not come forward.

Speaking to The Daily Telegraph, rural crime officer Marc Jackson said Wiltshire had been disproportionately affected due to its proximity to Stonehenge, adding that they were most commonly reported near to cultural heritage sites and busy main roads.