Mr Kouchner said many of the soldiers responsible were "Foresters" - residents of the Guinee Forestiere region of south-eastern Guinea - and that he had heard they were "recently reinforced by Liberian troops, former mercenaries".

BBC: France 'suspects Guinea leader'

Meanwhile a group calling itself the "Rassemblement des Forces Democratiques de Guinee" had been phoning international radio stations, and a hitherto unknown spokesman, Mohamed Lamine Fofana, had been claiming the attacks were the work of the Guinean opposition.

BBC: The Guinea conflict explained

John Guinee, an analyst at Stifel Nicolaus, said Mr. Thomas has a reputation for being an aggressive deal maker and successful real-estate investment banker, so the move could mean a "more aggressive management" style in the future that includes more acquisitions and asset sales.

WSJ: Boston Properties Names Thomas CEO