A killer who admitted murdering his girlfriend, her twin sister and a frail elderly couple lost an appeal today against an order that he must spend the rest of his life behind bars.

At the Court of Appeal in London, the Lord Chief Justice, Lord Phillips, rejected a challenge brought by former binman Mark Hobson, now 36, over his ''whole life tariff''.

Hobson pleaded guilty to the murders of his girlfriend Claire Sanderson, 27, and her sister Diane at a flat in Camblesforth, North Yorkshire, and also killing pensioners Joan and James Britton at their home near York.

At Leeds Crown Court in May, the judge hearing the case, Mr Justice Grigson, sentenced Hobson to life in prison and gave him a ''whole life tariff'', meaning he can never be freed on parole.

But it was argued on Hobson's behalf at a recent hearing before Lord Phillips and two other senior judges that he should have been given credit for his guilty pleas in the setting of a tariff.

Hobson's case set a legal precedent because a ''whole life'' tariff had never previously been imposed on someone who pleaded guilty. The reasons for today's decision will be released in a written judgment later today.

Sentencing Hobson, the trial judge said: ''You not only destroyed the lives of your victims, but you devastated the lives of those who loved them.

''The damage you've done is incalculable. The enormity of what you've done is beyond words.''

Hobson beat Claire Sanderson to death with a hammer before luring her sister Diane to her death a week later.

Shaven-headed Hobson subjected Diane to horrific sexual mutilation, possibly while she was still alive, before going on the run in July last year.

He then murdered house-bound Mr Britton, 80, and his wife Joan, 82, in their own home, brutally beating them both with Mr Britton's walking stick before stabbing them to death.

The Crown Court heard that Hobson had planned to slaughter even more people. The killer scribbled a list of other potential targets as police feared he might strike again.

The court was shown hand-written notes made by Hobson which suggested he had pre-planned the ''horrific and chilling'' murders and was even planning to kill the twins' parents George and Jackie.

Hobson's killing spree began when he battered his girlfriend 17 times with a hammer before putting a plastic bag over her head at the flat they shared in Camblesforth.

Friends and family had begged Claire to leave Hobson, whom she had been dating for 18 months, after she was subjected to a number of brutal beatings by her alcoholic boyfriend.

Mr Sanderson found his daughters wrapped in binbags on Sunday July 18 last year.

On that day Hobson, after taking a cocktail of cocaine, ecstasy, alcohol and cannabis, walked into the Brittons' detached house at Strensall, near York, and attacked them with a walking stick and a knife.

Hobson then went on the run for a week, sparking a massive manhunt.