In the six years since the young British woman Lucie Blackman was drugged, killed, dismembered and buried in a seaside cave in Japan, her family have become regular visitors to Tokyo.

Her father, Tim Blackman, has flown over Tokyo repeatedly from the time of her disappearance through the long trial of the man accused of killing her. Lucie's younger sister, Sophie, had handed out missing person leaflets and taken part in a reconstruction of her disappearance.

But today it was the turn of the person closest to her to speak out in public for the first time since her death - her mother, Jane Steare.

In a wrenching testimony at the Tokyo District Court, Mrs Steare spoke of the "unrelenting pain" caused to her family both by her daughter’s death and the terrible way in which her body was disposed of.

She appealed to the court for the maximum sentence to be imposed on Joji Obara, the Japanese property developer accused of killing Lucie and a young Australian woman, and of the drugging and serial rape of eight other women, both Japanese and foreigners.

In the latest sensational twist to the case, Mr Obara himself was absent from court today, having stripped himself naked and attached himself to the wash basin in his detention cell.

Lawyers acting on his behalf have recently approached both the parents of Miss Blackman and his alleged Australian victim, Carita Ridgway, offering between £200,000 and £300,000 to prevent them testifying in court.

"I spent seven months praying [Lucie] would be found [alive], but my worst fears came true when she was found not only dead, but her beautiful body had been chain-sawed into pieces, her beautiful long blonde hair had been shaved off, and her head had been encased in concrete," Mrs Steare told the court, struggling to control her emotions.

"I used to believe that the sorrow of any parent losing a child is the greatest sorrow anyone can know. I was wrong. To lose a child and know her body was desecrated in such an inhuman way is the greatest and most unrelenting pain I have ever had to endure. It is with me day and night."

"The fact that Obara has refused to attend court to face his today is very dishonourable and a clear sign of his guilt," she continued, speaking through an interpreter. "He is a coward."

Lucie Blackman was a 21-year old bar hostess in the Roppongi area of Tokyo when she disappeared in July 2000. But despite repeated appeals for information, by her family and by a visiting Tony Blair, nothing more was heard from her.

Then in February 2001, her dismembered body was found buried in a seaside cave a few hundred yards from an apartment owned by Mr Obara. Her head had been embedded in concrete, traces of which were found in his apartment.

A police officer who was called there by suspicious neighbours a few days after Miss Blackman’s disappearance described in court his refusal to allow a search of his property.

After his arrest, police found scores of videos in Mr Obara’s various properties, showing him having sex with drugged and insensible women.

Soon after Ms Blackman’s disappearance, the prosecutors allege, Mr Obara visited a series of shops and bought camping equipment, quick-drying concrete, mixing equipment, cutters, scissors, hammers, and a chainsaw.

He has admitted spending the evening before her disappearance with Miss Blackman at one of his seaside apartments.

But he insists that she died after taking illegal drugs provided for her by a dealer whom Mr Obara summoned to drive Miss Blackman home. The man in question died before the opening of the trial, and the only witness willing to corroborate his story is a self-described gangster boss.

"I have never accepted any count of the criminal prosecution," Mr Obara said in a written statement provided to The Times. "If I appear in court [today], I am afraid that I would be regarded as [guilty] ...this must reduce the criminal court to a venue for retaliation and criticism."

The head of the three judge panel, Tsutomu Tochigi, refused to allow the statement to be read in court. After Mrs Steare, the court heard testimony from Annette Foster, mother of Carita Ridgway, an Australian hostess who died in hospital in 1992. The prosecution alleges that she died as a result of chloroform which Mr Obara administered in order to rape her.

Mrs Steare was divorced from Lucie’s father Tim Blackman several years before her daughter’s disappearance, and has since remarried. "I was so proud to be a mother when she was born," she told the court. "I would watch her sleeping and wonder at the beauty of her little hands and feet."

"I’ll never see her face, hear her voice or stroke her beautiful hair ever again. I will never smell her lovely skin. I’ll never hear her laughter ... All I feel is this deep longing ache which never goes away."

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