The 22-year-old English language teacher was found buried in a bath of sand in a Tokyo apartment in March.

Speaking to the BBC, her parents Bill and Julia, from Brandon, Warwickshire, spoke of their struggle to come to terms with her death.

Mrs Hawker said: "Truly, some days we do not feel like surviving. It is the most appalling thing you can ever possibly have to deal with."

Her husband said the couple had decided to speak to the media to bring their daughter's brutal murder back into the public eye.

He said: "My daughter went to Japan to teach. She did not go to Japan to be murdered."

Holding up a poster of suspect Tatsuya Ichihashi, he said: "If anybody at all knows this man, please please do not hide it. He needs to be brought to justice."

He added: "When I was in Japan, the chief police officer assured me, made a personal pledge, that he would find this man and hunt him down."

The full interview will be broadcast on BBC1's Six O' Clock News on Wednesday.

Earlier this month, police officials released more CCTV footage of suspect Ichihashi, 28. He fled from officers when they called on him at his apartment on March 26 after the language school Miss Hawker worked for said it had been unable to reach her.