A Paris court has ordered the re-trial of a some members of a gang connected to the murder of young Jewish man, because their sentences were "too lenient."

Justice Minister Michele Alliot-Marie personally intervened to ask the French public prosecutor for longer jail terms.

Those who will eventually be retried will not, however, include Youssouf Fofana, 28, the ringleader of the gang, who was sentenced to a maximum sentence of life in prison, without possibility of parole for 22 years.

Mr. Fofana was the only defendant convicted of murder.

The court has now decided to re-try 14 of the 25 members of the gang who were sentenced to between six months suspended and 18 years in prison.

The new trial will take place in about a year.

"The 14 received sentences that were more lenient than those requested by the public prosecutor," a spokesman for the prosecution said

Fofana, the leader of the self-described French "gang of barbarians" was sentenced to life imprisonment for kidnapping and torturing Ilan Halimi, 23, for more than three weeks, until leaving him to die by some railway tracks.

The gang abducted Mr Halimi in 2006, apparently intending to hold him ransom. They tortured him until he was close to death and then left him, naked and bleeding, near a train station. He died shortly after he was found.

Fofana, who admitted killing Mr Halimi, was sentenced to life imprisonment, with a minimum period in jail of 22 years. Twenty-four other members were originally handed sentences ranging from six months suspended sentences to 18 years in prison — and two were acquitted.

The girl who apparently lured Ilan Halimi to his death was given nine years in prison, but under French law she could have been free in two years, despite the prosecutors requesting a minimum 10 year sentence.

A French magistrates’ union has criticised the government interference in the case in demanding a retrial.

“Justice is different from vengeance,” said Emmanuelle Perreux, the union’s president.