An Iraqi immigrant who battered to death a grandfather after taking Spice for the first time has been jailed for 15 years.

Iraqi Zana Yusif beat to death vulnerable Bangladeshi Tarek Chowdhury as both men were awaiting deportation at the Colnbrook Immigration Removal Centre in London.

The 32-year-old attacked Chowdhury in his cell on 1 December 2016 after he had stopped taking his medication and ingested Spice.

The defendant, who had only arrived at the centre two days before, was wearing no trousers when he followed the "soft, gentle and polite" 64-year-old into his cell to ask him for a light.

The 5ft 2ins tall victim was punched around 12 times at around 9am in Cell Five based in the centre in Harmondsworth, West Drayton, Greater London, and rushed to hospital.

Chowdhury died the same day just before 9.30pm and Yusif was arrested and charged with murder.

Judge Richard Marks QC said Spice, a type of synthetic cannabis, was a drug which was associated with hallucinations and aggression.

"It is clearly the case your ingestion of Spice the day before these events must have played a significant part in your actions in carrying out this killing," he said, according to the Daily Mail.

"Even if it was the first time you have taken Spice it was in my judgment a gravely irresponsible thing for you to have done."

The Old Bailey heard how Yusif was violent towards inmates and staff while on remand at Wormwood Scrubs and the judge added he should be deported at the end of his sentence after he was convicted of manslaughter by diminished responsibility.

The court heard how Chowdhury had come to Britain in 2003 because of his political beliefs and was found by authorities working illegally in a fish and chip shop in the West Midlands.

The defendant had mainly lived in London after being smuggled into the country in the back of a lorry when he was 17 to avoid being conscripted into the Iraqi army.

The court heard that Yusif had convictions for 33 offences of dishonesty, violence and harassment and had battled mental health problems.