(CNN) Two British senior citizens were removed from a Caribbean cruise ship and arrested after a "large amount of cocaine" was discovered in their cabin.

The 70- and 72-year-old suspects are being held by police in Portugal, the UK's Press Association news agency reported.

The Marco Polo ship, operated by Cruise and Maritime Voyages, had returned to Europe from a cruise around the Caribbean.

The septuagenarians, who are thought to be a couple, were detained in Lisbon after Portugal's Policia Judiciaria received information from the UK's National Crime Agency.

A Foreign and Commonwealth Office spokesperson told CNN that: "Our staff are in contact with the Portuguese authorities following the arrest of a British man and woman in Lisbon."

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