The court of appeal has doubled the amount of time a man who was responsible for Ireland's worst fatal road collision must spend in jail.

Shaun Kelly, 27, from Ballymagan, Buncrana, Co Donegal pleaded guilty last year to dangerous driving causing the deaths of eight people in July 2010.

He was sentenced to four years in jail with the last two years suspended.

The Appeal Court ruled that sentence was unduly lenient and this afternoon it ruled the appropriate sentence was eight years with the final four suspended.

Seven of those who died were young men aged between 19 and 23 who were passengers in Kelly's car.

The eighth was a 66-year-old man on his way back from bingo.

Giving the Appeal Court's judgment, Mr Justice George Birmingham said the collision on 11 July 2010 had had devastating consequences.

If the matter had gone to a full trial in which Kelly had pleaded not guilty, he said the maximum sentence of ten years, or close to that sentence would have to have been considered.

The judge said the aggravating factors were the multiple fatalities, the prolonged persistent and deliberate course of very bad driving in the run up to the collision, the overcrowding of Kelly's car, the overtaking and failing to heed a warning.

He said the culpability was very high and the harm caused enormous.

In mitigation, the court said it was taking into account Kelly's youth, his plea of guilty and the significant injuries that Kelly himself had sustained.

The judge said there was disagreement about the severity and long-term effect of Kelly's injury but its impact could not be ignored.

He said there was real remorse and what had happened would affect Kelly for the rest of his life. The judge noted that one of the bereaved families had said that Kelly was five-and-a-half years into a life sentence.

He said the attitude of some of the families was extraordinarily generous but did not determine the sentence of the court.

The judge said he was also taking into account testimonials handed in on Kelly's behalf which spoke of his previous good character apart from a dangerous driving conviction.

The judge said the court took into account the fact that he was already some way into his sentence and he took into account the fact that it appeared that some of the bereaved families may have encouraged him to contest the case which would have had an effect on the timing of the guilty plea.

In all the circumstances, the court suspended four years of an eight year sentence.

Kelly was disqualified from driving for ten years.

The judge said the court had decided not to increase that period. He said if the court was to do so it would make it more difficult for Kelly to take a position as a responsible member of society after his release.