The lorry was being driven from Frankfurt to the Yorkshire Wildlife Park near Doncaster, where the 22-month-old bear Nissan – originally from Moscow – is being resettled.
Officers arrived 10 minutes laterand ordered the three migrants out of the vehicle – taking care not to distress the huge and potentially deadly animal beside them.
A witness told The Sun: ‘It only took 17 seconds before four vaulted the barrier and prised open the truck’s back doors.
‘They must have had the surprise of their lives. It shows how desperate they are to get to Britain.’
Simon Marsh of Yorkshire Wildlife Park added: ‘There was a slight hiccup at Calais. Nissan had some unexpected guests in the back of the lorry. Obviously he was in a crate, so it was all very safe and secure, but I think they were a bit surprised when they saw a polar bear.
‘It’s not probably what they were expecting when they opened the back of the lorry. Even at two years old he’s a big animal and he can be very dangerous.’
Asked what the danger would have been if Nissan had not been in his cage, he said: ‘I think a lot of people in Calais would have been in trouble if he hadn’t been in his crate.
‘It’s obviously not ideal when people get in to the back of a lorry with a polar bear.’
Nissan was born at Izhevsk Zoo in central Russia and later moved to Moscow Zoo, but earlier this week he was flown to Germany in order to be taken to Yorkshire.
