This stunt - with two people clinging to the back of a bus in Blackpool - has been branded 'crazy' by shocked onlookers.
A picture shared on Twitter appears to show the pair hanging on the the vehicle as it travels around the town centre.
Reportedly taken on Friday night near the Houndshill shopping centre, it was posted with the comment: "Saves on the price of a ticket I guess."
Another Twitter user said they saw the duo near the Winter Gardens, calling their actions 'totally crazy'.
A Blackpool Transport spokesman said: "We have seen a huge rise in anti-social behaviour in recent weeks including over 20 smashed windows and this seems to be the latest craze.
"We're asking our drivers to be extra vigilant and we are actively working with the authorities to report these dangerous acts.
"We're reviewing CCTV of all incidents and will work to take the most appropriate action in all cases of anti-social behaviour. It isn't just the children who are endangering themselves it's other road users too."