Russian and Ukrainian forces are interlocked in desperate battles for control of Ukraine's eastern towns of Pokrovsk and Myrnohrad, which Moscow considers a gateway to the remaining unoccupied areas of the Donetsk region. On Sunday, Valery Gerasimov, Russian chief of staff, told President Vladimir Putin his 2nd and 51st Combined Arms Armies were advancing along converging axes and have completed the encirclement of the enemy in Pokrovsk and Myrnohrad.