North Korea is celebrating the 113th birthday of its late national founder Kim Il Sung, grandfather of the current leader Kim Jong Un.
North Korea regards April 15 as its most important public holiday.
Tuesday's edition of the country's ruling Workers' Party newspaper Rodong Sinmun carried an editorial praising the founder's achievements and calling for loyalty to Kim Jong Un.
State-run media said celebratory events will be held in the capital Pyongyang in the evening.
NHK filmed the North Korean side of the border river on Tuesday morning from Dandong in northeastern China.
The footage showed people entering and leaving a facility displaying a portrait of Kim Il Sung.
North Korea has been rapidly deepening military cooperation with Russia. It has sent troops to Russia, which is still fighting after invading Ukraine.
Observers say North Korea's relations with China, which is seen as its biggest backer, have become shaky. They also say this has had a negative effect on the economy.