The sister of Nick Dunn, one of the six ex-servicemen arrested in India for weapons offences back in 2013, has spoken out about her brother's imprisonment.  

The "Chennai Six" were among 35 crew members sentenced by an Indian court to five years in prison in January, for carrying unlicensed firearms.

The six men were all former soldiers - Nick Dunn from Northumberland, Billy Irving from Argyll, Ray Tindall from Chester, Paul Towers from East Yorkshire, John Armstrong from Wigton in Cumbria and Nicholas Simpson from Catterick.

The crew were working for American company, AdvanFord, an anti-piracy security company protecting commercial ships off the coast of Africa in the Indian Ocean, when the MV Seaman Guard Ohio (above) was detained and weapons found on board.

The company insists that the ship was in fact in international waters, and was carrying weapons for security purposes.

The charges were quashed in July 2014, but the crew's passports were detained by the Indian government, meaning they were unable to leave the country.

The police appealed, and this January the men were sentenced to five years in prison.

Their prison conditions are said to be dire. Dunn has previously said that the men sleep on concrete in cells infested with snakes and rats, using a hole in the ground for a toilet.

The Foreign Office has raised the issue several times with the Indian Government, with more than 20 MPs consistently maintaining their innocence; Theresa May has also taken up the case.

A petition calling for the soldiers' release has gained more than 375,000 signatures.

The case has now progressed to a higher appeals court in India.

Lisa Dunn said of her brother's imprisonment:

"This is now the fourth Christmas that these men have been torn apart from their families. We're trying our hardest to keep a sense of positivity, but Christmas unfortunately is irrelevant to us and it's irrelevant to the men." 

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