Chechen rebel leader Doku Umarov claimed responsibility for the Moscow bombings in the name of Islam.

VOA: special.2010.04.03

The most recent Chechen claim of responsibility was posted on the Internet on behalf of separatist leader Doku Umarov.

VOA: standard.2009.12.12

Meanwhile,Chechen Islamist rebel Doku Umarov, dressed in a military camouflage jacket in a wooded location,claimed credit for the Moscow subway bombings in an Internet video posted on Wednesday.

VOA: standard.2010.04.01

Ernest Doku, telecoms expert at comparison site uSwitch.com, said with speeds now seven times faster than 3G, it could convince more mobile users to move to 4G.

BBC: 4G mobile broadband speeds 'doubling', says EE