Ukraine's President Says Russian Forces Have Been 'Brought Into Ukraine'

Ukraine's president said on Thursday that Russian troops had entered his country in support of pro-Moscow rebels who captured a key coastal town, sharply escalating a five-month-old separatist war.

President Petro Poroshenko told a meeting of security chiefs that the situation was "extraordinarily difficult ... but controllable" after Russian-backed rebels seized the town of Novoazovsk in the southeast of the former Soviet republic.