Detectives are speaking to the driver and owners of a lorry after 16 people were discovered in a sealed trailer onboard a ferry.

The Stena Line ferry arrived in Rosslare in Co Wexford on Thursday afternoon from Cherbourg in France.

Police confirmed they were probing possible immigration offences and seized a truck involved in the incident.

The men were found by an employee who heard banging on the side of the trailer. They are all in good health, the ferry company and police said.

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Two ambulances and several doctors’ cars and police cars drove onto the ship’s vehicle deck shortly after it docked in south-east Ireland.

A large police and Immigration Bureau presence was visible around the port.

Emergency services at the scene Emergency services at the scene (Niall Carson/PA)

Irish police said: “An Garda Siochana are now investigating all the circumstances of this incident.

“The articulated truck involved in this incident has been detained.

“The driver and the owners of the articulated vehicle are assisting An Garda Siochana with our inquiries.”

The force said all the individuals appeared in good health and were receiving medical assessments after arrival at Rosslare, one of Ireland’s main sea ports for passengers and freight.

It added: “Garda Immigration Officers attached to Wexford Garda Station, supported by the Garda National Immigration Bureau (GNIB) will carry out an assessment on the immigration status of all the persons.”

Ian Hampton, Stena Line’s chief people and communications officer, confirmed an employee discovered the people during a routine inspection shortly before 10am on Thursday.

He said: “During the Stena Horizon’s 9pm sailing from Cherbourg, France, to Rosslare in the Republic of Ireland on Wednesday November 20, one of our employees during a routine inspection discovered 16 people in a sealed trailer on the vehicle deck.

“All the individuals are reported to be in good health and have been moved to a private passenger lounge on the ship where their wellbeing is the focus of our employees.”

The incident comes just days after a group of 25 people were found inside a refrigerated container on board a UK-bound ship just off the coast of the Netherlands.

Last month, 39 people were found dead inside a container in Essex which had arrived in the UK via a ferry from Zeebrugge, Belgium.

Taoiseach Leo Varadkar told broadcaster RTE: “Of course our initial response will be a humanitarian one, to make sure those people are well and that their health is good.

“After that of course there will need to be a response that involves the gardai, because as you know human trafficking is illegal, and we’ll need to see what happens with the people who come ashore.”

Opposition party Fianna Fail’s spokesman on justice Jim O’Callaghan expressed his shock and demanded a full investigation into the incident.

“A full investigation must be launched into the discovery of up to 16 people being transported in the back of a lorry to Ireland,” he said.

“Human trafficking is a modern form of slavery and needs to be tackled with fully resourced policing.

“Recent events show unfortunately Ireland is playing a significant part in this crime. These traffickers have to be thoroughly policed so vulnerable people are protected.”