Pair plundered HMS Hermes shipwreck in Dover Strait
Two men have been found guilty of failing to declare items worth £80,000 taken from a sunken World War One Royal Navy warship.
John Blight, 58, and Nigel Ingram, 57, denied taking any items from the wreck of HMS Hermes, which sank in the Dover Strait in 1914 and claimed 44 lives.
About 100 artefacts were found in Ingram's home, and others were found at Blight's residence.
The pair were convicted by a jury at Canterbury Crown Court.
Previously, the court heard the items seized included ships' bells, a torpedo hatch, launch panel, metal ingots and chinaware which had not been declared, as well as about £16,000 in cash.
The pair used winching equipment to remove some of the items and sold them as scrap in the "commercial exploitation of shipwrecks".
Addressing Blight during sentencing, Judge Heather Norton said: "You acted together, you and Mr Ingram, to pillage the wreck without the knowledge of the maritime authorities, and scrapped items for financial gain."
She described the pair as "submarine pirates" and said by taking the items, they had "damaged the story of the vessel, the story of the people who served on it, the story of the country, and the story of all of us".
Ingram, of London Road, Teynham, Kent, was charged with four counts of fraud and an additional charge of being in possession of criminal property and was found guilty on all five counts.
He was sentenced to four years in prison.
Blight, of Old River Way, Winchelsea, East Sussex, faced four counts of fraud between 2010 and 2015 and was found guilty on two charges.
He was sentenced to three and a half years in prison.
Mark Harrison, head of heritage crime for Historic England said "part of our national story is lost and can never be replaced".