A 21-year-old man has been arrested in connection with the murders of French students Laurent Bonomo and Gabriel Ferez, Scotland Yard said.

The friends, both 23, were bound, gagged and stabbed to death in a bedsit in New Cross, south London on Sunday night.

The Metropolitan Police said the man was arrested at 3.40am and is in custody at a police station in south-east London.

The two friends were living in the capital while they worked on a three-month research project at Imperial College London.

Mr Bonomo, from Velaux, near Marseille, and Mr Ferez, from Prouzel, near Amiens, were due to return home later this month.

Police have said the men might have died for the sake of two handheld games consoles.

Detectives said two Sony PSP consoles, costing £130 each, were stolen from Mr Bonomo's rented flat in Sterling Gardens, New Cross, south London.

Officers are also hunting a black Packard Bell laptop taken in the previous burglary while Mr Bonomo was in the shower.

Mr Ferez, who lived in South Norwood, had travelled to spend the evening at his friend's flat, where they were playing computer games.

Det Chief Insp Mick Duthie, leading the investigation, said: "The more we find out about them (the victims) the more we find they were good, honest, hard working young men; very intelligent, never caused anybody any problems, they were well liked and come from respectable families. This is just a tragedy."

A pathologist documented 243 separate injuries to the badly-burned bodies, with Mr Bonomo suffering 80 wounds after he died. It is believed the Frenchmen were dead before the fire started.

Neighbours dialled 999 after an explosion blew the windows out and ignited a fierce blaze shortly after 10pm. They called out to find out if anybody was in the flat but nobody responded.

Mr Bonomo's fiancee, Mary Bertez, has vowed to avenge his death.

She wrote on a social networking site: "I will never stop thinking about you for a second. I had 10 months of a happiness I had never experienced until then.

"I will give all the required information to the investigation, my dear, so you can be avenged."

Officers said on Friday they were following up on about 25 calls which have been received in relation to the murders.

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