Chaos in Ukraine as Russian fighters take separatists' HQ

An armed pro-Russian separatist stands guard on a street outside the regional administration building in the east Ukrainian city of Donetsk

Roland Oliphant in Donetsk

Ukraine's rebel movement was plunged into crisis yesterday after pro-Russian fighters backed by armoured personnel carriers seized the movement's headquarters in Donetsk and destroyed the barricades protecting it.

The surprise move by a group called the Vostok Battalion, a heavily armed rebel unit that has been involved in fighting against the Ukrainian army, sparked speculation about an internal coup within the fractious rebel movement.