Ambulance staff have been seen giving oxygen to a man after 18 migrants were found on a ferry in Dover

The arrivals were discovered aboard the Cotes des Dunes vessel at about lunchtime on Tuesday on arrival at the busy trade port, the PA news agency understands.

The Port of Dover said they were found inside a lorry that had arrived on board the cross-Channel ferry from France.

Nine people have been taken to hospital as a precaution while the remaining nine have been transferred to the Border Force.

The incident came amid rough weather in the English Channel on Tuesday, with wind gusts of up to 38mph in the Kent port, conditions likely to make crossing the Dover Strait in inflatables difficult.

Pictures show at least six ambulance vehicles in the port, with police and Border Force officers also in attendance.

A spokesperson for South East Coast Ambulance Service (SECAmb) confirmed ambulance staff were on the scene “following reports of a number of people in need of medical attention”.

Kent Police confirmed they were called shortly before 12pm to assist Home Office immigration enforcement following a report that suspected migrants had arrived on a vessel.

The Cotes des Dunes, operated by DFDS, sails between Dover and Calais and has returned to service.

Tuesday’s incident in Dover comes on the day it was announced that Border Force officers could be given powers to turn migrants away from the UK while at sea, under laws proposed as part of sweeping reforms of the asylum system.