Authorities in the Netherlands discovered 25 illegal migrants hiding inside a shipping container on a cargo ferry bound for the United Kingdom.

The Britannia Seaways vessel had left Vlaardingen shortly before dozens of stowaways were found in a refrigerated tractor-trailer, forcing the ship to return to port, where it was met by emergency services and at least 20 ambulances, NOS reports.

Officials say the migrants had somehow made a hole in the container and climbed inside.

Photographs of the group indicate they are primarily "young men," according to Reuters.

Dutch police say they believe most of the migrants are from Iraq and Kuwait, but are still investigating.

De verstekelingen die gisteravond aan de Vulcaanhaven in Vlaardingen uit een koelcontainer van een vrachtschip werden gehaald, komen vermoedelijk uit Koeweit en Irak. De 39-jarige chauffeur uit Roemenië is aangehouden. https://t.co/18vwilEbkU — Politie Rotterdam eo (@Politie_Rdam) November 20, 2019

“The strangers who were found yesterday in a refrigerated container on a cargo ship probably come from the Middle East, mainly Kuwait and Iraq,” police explained in a statement.

“The investigation into the determination of identity is still ongoing, so the definitive origin cannot yet be determined with certainty.”

All of the migrants have been transferred to the custody of Department of Alien Identification and Human Trafficking.

The driver of the vehicle, a 39-year-old Romanian man, has been arrested.

In October, U.K. authorities discovered the bodies of 39 Vietnamese migrants inside a refrigerated container that had arrived via ferry from Zeebrugge, Belgium.

David Knight joins The Alex Jones Show to break down the federal ruling that upheld the illegal sale of fetal tissue.

(PHOTO: MARCO DE SWART/ANP/AFP via Getty Images)