The loved-ones of a group of British veterans currently imprisoned in India are marking the fourth anniversary of their arrest by stepping up their campaign to free them.

The  'Chennai Six' were working on an anti-piracy vessel protecting shipping from Somalian pirates in 2013, when they were detained by the Indian Coastguard, who accused them of carrying firearms without permits.

Now, four years on from their arrest, their families have handed a petition to Downing Street to demand that the government does more to aid their release.

Chennai Six

John Armstrong, 30, Nick Dunn, 31, Billy Irving, 37, Nicholas Simpson, 47, Ray Tindall, 42 and Paul Towers, 54, were sentenced to five years in prison in 2016.

The campaign to secure the group's freedom has been supported by Prince Charles, Prince Harry and Joanna Lumley.

MPs from each man's constituency werer present at the lobby, alongside their family members.

Billy Irving's two-year-old son delivered the petition, which has 405, 000 signatures, to number 10.

The fiancee of Billy Irving, one of the six, said she thinks about marrying him "every single day" as she took her justice campaign to Number 10.

Yvonne MacHugh, is engaged to the former member of 1 Para, and was accompanied in Downing Street by their two-year-old son William, whom he is yet to spend a day at home with.

She said William has now been to India three times to visit his father.

Ms MacHugh said the Government's efforts "aren't good enough", adding:

 "I want them to openly say 'We know the men are innocent, release them now'.

Ms MacHugh, 28, said William is the best thing that has ever happened to her, adding:

"He's shown me that I've got to be strong, and I can be strong. But it is horrific. Every single day ... I'm now a single mum."

Ms MacHugh said they got engaged when she brought William over to India to visit Mr Irving for the first time.

The pair had planned their wedding for May 2016 when they thought her fiance would be home.

"It would be both a homecoming celebration and our wedding celebration,"

She added that she has not lost hope and said she thinks about it "every single day".

"Definitely. It will happen. I just want it to happen tomorrow, and not in five years time."

"We don't know what to do to have him released. We don't know if what we're doing is right. We don't know if it's wrong.

"But we just know we have to do something, and we're trying to do everything we can to bring him home."

Ms MacHugh said she sends lots of photographs to her fiance, writing to him every week, and talks to her son about his father every day.

"We watch home movies of his dad, and pictures and everything, so that he doesn't forget him.

"And that when he does come home he knows that that's the dad who loved him and has loved him from day one," she said.

Ms MacHugh said her fiance writes bedtime stories for William which she reads to him at night.

She said they are hoping for a strong response from governmemt.

"Boris Johnson has said in the past that he will leave no stone unturned to release the Chennai six.

"And really we are just hoping that he backs that up with actions."