Pro-Russia rebel build-up near port city alarms Ukraine military

Burnt-out vehicles are seen at a residential sector in Mariupol, a city on the Sea of Azov, eastern Ukraine February 3, 2015. REUTERS/Gleb Garanich

KIEV/SAKHANKA, Ukraine (Reuters) - Pro-Russian separatists are building up forces and weapons in Ukraine's south east and the Ukrainian military said on Saturday it was braced for the possibility of a rebel attack on the port city of Mariupol.

The Kiev military accused Russia on Friday of sending more tanks and troops towards the rebel-held town of Novoazovsk, further east along the Sea of Azov coast from Mariupol, expanding their presence on what it fears could be the next battlefront.