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A man jailed for at least 17 years for driving through a crowd of partygoers and killing two teenagers has continued his violent ways behind bars.
Lipine Sila, 23, was sentenced last week for the murder of 16-year-olds Jane Young and Hannah Rossiter, and causing grievous bodily harm to eight others in the Christchurch suburb of Edgeware in May last year.
In court today, Sila admitted headbutting a prisoner unconscious in an unprovoked attack at Christchurch Men's Prison in January.
Judge Graeme Noble also revealed that Sila had two previous convictions of assaulting a female, along with two other assaults, back in 2006.
The court heard that while in prison on remand, Sila walked up to a fellow inmate in D Block, where he was sitting at a table, and without warning head-butted him on the right side of his head.
The victim fell backwards from his chair, unconscious, and was taken to Christchurch Hospital for treatment. He suffered a sore neck and a number of headaches.
In explanation, Sila admitted slapping the victim with an open hand, saying he had heard the victim calling someone else a "nigger", and it was an accident.
Sila was remorseful and did not try to excuse himself in any way, said his lawyer Lee Lee Heah.
Judge Noble sentenced Sila to six months' imprisonment for the assault, but it will not add to his existing 17-year sentence.
Sila was "no stranger to violence" when this occurred, the judge said.
The assault would no doubt be taken into account by the Parole Board somewhere down the track.
A charge of driving with excess breath alcohol against Sila was withdrawn by police today.
