FSB chief says Moscow bombs 'linked to North Caucasus'

Federal Security Service (FSB) chief Alexander Bortnikov says female suicide bombers, believed to have carried out two attacks on the Moscow Metro, had links to the North Caucasus region.

At least 38 people were killed and more than 60 injured in two attacks on the Moscow Metro during the morning rush hour, officials say.

No group has yet claimed responsibility for being behind the attacks.

But Russian security services say the attacks had links to militant groups in the North Caucasus region.