Complex sentence: In February 1944 near the end of World War II Russian Army and NKVD units flood Chechen-Ingush ASSR, the maneuvers were disguised as military exercises of the southern district.
Split into simpler sentences: In February 1944 near the end of World War II Russian Army and NKVD units flooded Chechen-Ingush ASS. Tthe maneuvers were disguised as military exercises of the southern district.