Yonhap News Agency of the Republic of Korea (RoK) and the specialist outlet NK News reported that it was not known whether the DPRK leader was on board the train.
Security was tight before the train's arrival with police cordoning off the riverfront some 100 metres yards from the bridge with tape and metal barriers.
On February 23, the Vietnamese Ministry of Foreign Affairs announced that Kim Jong-un will pay an official friendship visit to the Southeast Asian nation in the coming days.
The visit is made at the invitation of General Secretary of the Communist Party of Vietnam Central Committee and President of Vietnam Nguyen Phu Trong.
Vietnam is making meticulous preparation for the second summit between the DPRK leader and US President Donald Trump, which is slated to take place in the capital city of Hanoi on February 27 and 28.
