KOSTYANTYNIVKA, Ukraine (AP) — Masked and armed militants have seized a government building in yet another city in eastern Ukraine, expanding their onslaught in the region.

The building housing the city hall and the city government in Kostyantynivka, just 100 miles from the Russian border, was seized today by masked men who carried automatic weapons. An Associated Press photographer saw about 15 armed men, some of them wearing St. George's ribbons, a symbol of the pro-Russian movement, guarding the building.

Kostyantynivka is just 35 kilometers south of Slovyansk which has been in insurgents' hands for more than three weeks now. The militias in Slovyansk are keeping seven OSCE military observers hostage there.

Since November, Ukraine has been engulfed in its worst political crisis since the 1991 fall of the Soviet Union.

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