KYIV, Ukraine (AP) – Ukrainian troops are locked in intense battles with the advancing Russian army in two border areas, President Volodymyr Zelenskyy said, while the death toll from a Russian apartment building collapse blamed on Ukrainian shelling rose to 15. Zelenskyy said “fierce battles” are taking place near the border in eastern and northeastern Ukraine as outgunned and outnumbered Ukrainian soldiers try to hold back a significant Russian ground offensive. “Defensive battles are ongoing, fierce battles, on a large part of our border area,” Zelenskyy said in his nightly video address Sunday.