A DANGEROUS knife thug freed from jail by mistake was jailed for life with a minimum of 40 years for the “sadistic” murders of two brilliant French students.

Dano Sonnex and his accomplice, Nigel Farmer, were told by judge Mr Justice Saunders they had only escaped being jailed for the rest of their lives for the “truly horrific” murders because of their young ages.

Biochemists Laurent Bonomo and Gabriel Ferez, both 23, were knifed 244 times by Sonnex, 23, and drug addict Nigel Farmer, 34, during a three-hour torture ordeal.

Sonnex had been jailed for a previous knife attack but was allowed out on licence and went straight back to his life of crime.

Yet instead of being recalled to prison he was left free to kill after what was described as a “complete breakdown in communication”.

It was 16 days before police came to take Sonnex into custody on June 29 last year – but they were too late.

The students already lay dead at Mr Bonomo’s bedsit in New Cross, south London, in a scene of “almost unimaginable horror”.

Mr Bonomo – who Farmer later said “just wouldn’t die” – was stabbed 194 times and Mr Ferez suffered 50 knife wounds, some of them after his death.

Justice Secretary Jack Straw has apologised to the families of the victims.