A man who murdered his girlfriend by punching, kicking and stamping on her before falling asleep and leaving her to die has been sentenced to life in prison with a minimum term of 21 years.

Raj Sidpara, 50, was convicted of the murder of Tarnjeet Riaz, also known by her maiden name Chagger, at Leicester crown court last week.

The court heard that Riaz was found with extensive trauma to her face, as well as multiple broken ribs and bleeding on the brain, when she was found unresponsive at Sidpara’s home address.

Judge Harbage said Sidpara attacked Riaz “in a savage and merciless way”.

“You punched, kicked and stamped on her in a sustained attack,” he told the defendant. “Your conspicuous lack of remorse at any stage was quite remarkable. You have steadfastly refused to explain what you did or why.”

Sidpara, who has been diagnosed with an alcohol dependence syndrome, had pleaded guilty to manslaughter in October but denied murder.

He was accused of attacking and killing Riaz in the early hours of 6 May after a night out, and initially told police she had fallen over while drunk. After the attack he went to bed and slept until the morning.

When Sidpara called emergency services on the afternoon of 6 May, Riaz was already dead.

The court heard that the couple had been in a relationship for about five months, and that Sidpara was “prone to outbursts of anger”, the BBC reported. He had 24 previous convictions for various different offences, including for violence, threats to kill, and harassment and assault of previous girlfriends.

Riaz’s brother, Balraj Chagger, said: “Tarnjeet, or Taz as we knew and loved her, was always there for us and yet when she needed us most, we could not help her. We had no idea how bad things were and this feeling will haunt us for ever.

He added: “Raj took advantage of a woman half his strength and his cowardice and violence cost Taz her life and has shattered our lives forever. There was no emotion and no remorse from Raj for his actions. To think my sister was in a relationship with this monstrous man and to think how he had treated her – all Taz ever wanted was to be loved.

DI Emma Matts, the senior investigating officer in the case, said: “Tarnjeet was killed at the hands of someone she was in a relationship with. Someone who should have supported and protected her, not someone she should have feared would brutally attack her.

“While the person responsible will now spend many years behind bars, Tarnjeet’s family are left with so many questions and the overwhelming feeling of wondering if they could have done more.”