Two Mongolian border guards in Tsagaan-Uul soum, Khovsgol aimag were shot dead on May 5 when they were on duty at the border with Tuva Republic of Russian Federation. B. Monkhoo, a sergeant-major in the same army unit, has been missing since then.

The Border Defense Authority (BDA) has said the suspected killer is likely to be heavily armed with 200 combat bullets, and a rifle. He is also believed to have two horses with him.