LONDON, England (CNN) -- Two British men were convicted Thursday of torturing and killing two French students in London last June, London's Metropolitan Police said.





Gabriel Ferez (left) and Laurent Bonomo were graduate biochemistry students at London's Imperial College.





Nigel Farmer, 34, and Daniel "Dano" Sonnex, 23, were also found guilty of arson, false imprisonment and burglary.





The bodies of Laurent Bonomo and Gabriel Ferez, both 23, were found in Bonomo's burned apartment in southeast London last summer.





Ferez's mother, Francoise Villemont, told the judge that her son's killing was "indescribable and inexcusable."





"No human being deserves such a death," she said. "My life stopped on the 29th June 2008. I feel battered and bruised as a mother forever scarred."





The lead detective in the case, Mick Duthie, said at the time that the two had fallen victim to a "frenzied, brutal, horrific attack."





During a five-week trial, the jury heard details of how the two students were tied up for hours, tortured for their credit-card personal identification numbers and repeatedly stabbed in an early morning attack June 29, 2008.





Farmer went back to the apartment that night and set fire to it in an attempt to destroy the evidence, police said. Emergency services were called to the address after neighbors heard an explosion and saw flames leaping from the premises.





Investigators initially believed the French men died in the fire, but an autopsy showed each had been stabbed dozens of times in the head, neck and torso -- 196 times, in Bonomo's case and 47 times for Ferez.





Police believe they were bound during the assault and an accelerant was used to start the fire after they were killed.





Hand-held Sony portable games, mobile phones and credit cards were missing, police said.





Bonomo's card was used to withdraw £360 (about $580) in seven transactions. A bank machine seized Ferez's card when someone tried to use it.





Farmer turned himself in to police in the early hours of July 7, 2008, "demanding to be seen and claiming to have committed a double murder. After hospital treatment, he was questioned for three days but chose to say nothing to police," Duthie said.





Police appealed to the public for tips, prompting someone to name Sonnex as someone "with a propensity to use violence and whose family lived very close by," the police said in a statement.





Farmer and Sonnex were arrested in July.





Bonomo's father, Guy Bonomo, said he is "tormented" by images of his son's suffering. "Not only have you taken Laurent's life, you've taken my heart and soul," he told Farmer and Sonnex.





"I wish from the bottom of my heart that you will stay in prison for the rest of your lives. I can't bear to think that someone so evil will walk the streets again, that my daughter or a member of my family could encounter you again."





In court, each blamed the other for killing the two men, police said.





"Throughout the case, neither has had the decency or courage to admit any part in the fatal assault on the two students with both men telling different stories and ultimately blaming each other," Duthie said. "I'm sad to say that we have not yet heard what did happen that early morning."





The two men are due to be sentenced later Wednesday.





The victims were biochemistry graduate students on a three-month course at Imperial College, London, studying genetic developments. They were planning to return to France in July.
Who was killed? What did investigators initially believe?
students the French men died in the fire,
question: Who was killed?, answer: students | question: What did investigators initially believe?, answer: the French men died in the fire,