A killer who repeatedly punched his five-year-old stepson against a metal fence as the boy pleaded for his life, will serve three more years in jail.

Marvyn Iheanacho , 39, beat his partner's five-year-old son, Alex Malcolm, to death after he lost a trainer on November 20 last year.

The boy, who has been described as a "special little boy" by mother Lilya Breha, never regained consciousness after the attack and died in hospital two days later after sustaining head and stomach injuries.

Iheanacho, who had denied murdering Alex, was originally sentenced to life in prison with a minimum term of 18 years following a trial at Woolwich Crown Court in July, but the sentence was appealed by solicitor general, Robert Buckland who labelled it as "unspeakable violence".

He said: "The unspeakable violence that this young boy was subject to is truly appalling."

Adding: "As a result, a vulnerable little boy was murdered by someone in a position of trust.

"I hope the increased sentence gives some comfort to Alex Malcolm’s family."

Court of Appeal judges have now ruled the 18 year sentence as too lenient, extending the minimum time Iheanacho must serve behind bars.

Iheanacho, of Wesley Avenue, in Hounslow, watched the proceedings via videolink from prison on Tuesday (October 17) as Lord Justice Treacy, Mr Justice Jay and Mr Justice Warby agreed with solicitor general Buckland that 18 years was "unduly lenient".

Lord Justice Treacy announced the jail term would be increased to 21 years, saying: "In our judgment the minimum term of 18 years did not adequately reflect the serious aggravating features of this case, which relate not only to the offence itself but also to the offender's past violent criminal conduct."

Marvyn Iheanacho has previous convictions for violent crime

His previous convictions showed he had a "deeply entrenched streak of violence within him".

He also said Iheanacho was in a position of trust and did not seek medical assistance for the boy "when it was clear he required urgent care".

The trial heard how witnesses to the attack described hearing the boy saying "sorry" as loud banging rung out and the man screamed about the loss of a shoe during the attack at Mountsfield Park in Catford, south-east London.

Police later found one of the boy's trainers in the play area.

Iheanacho has a number of previous convictions for offences including attacks on ex-partners and robbery.

With his minimum term now increased, Iheanacho will have to serve 20 years before he is eligible to apply for parole and due to time on remand, he will have to spend at least 20 years and 119 days behind bars.

Children's charity, NSPCC, has reminded anyone who is concerned about a child to call their helpline, a spokesman said: "This was an appalling and grave offence which saw a young child brutally murdered.

"Iheanacho should have been caring for Alex, but instead he violently robbed him of the chance to live a long and happy life.

"Babies and young children are entirely dependent on those who care for them and we all have a duty to look out for their welfare.

"We urge anyone concerned about a child should call the NSPCC Helpline on 0808 800 5000 as it could save a life."

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