Policeman Shi Xianqiang patrols the border between China and Russia on frozen Heilongjiang River near Luoguhe Village in Beiji Town of Mohe City, northeast China's Heilongjiang Province, Jan. 9, 2021. Shi Xianqiang and his wife are both police officers responsible for patrolling the border between China and Russia at Luoguhe, one of China's northernmost villages. (Xinhua/Xie Jianfei)