Men look out of a the window of a train that travels across Friendship Bridge from North Korea to China's Dandong, Liaoning province. Photo: Reuters/Thomas Peter

Large screens reportedly put up by North Korean authorities at a key railroad bridge with China are spurring rumors that leader Kim Jong-un has made secret visits to China and Russia. The last time such preparations occurred is said to be when late leader Kim Jong-il visited China in 2011.

South Korean news service Daily NK has quoted a North Korean source as saying the screens at Dandong Station near the Sino-Korean Friendship Bridge were erected about a week ago. The barriers reportedly block views of any trains that cross the bridge. The police are also “conducting drills” with traffic barricades.

“Since then there have been rumors [Kim Jong-un] made a stopover in China on his way to Russia,” the source said.

The traffic barricade drills were reportedly conducted on Sunday morning and afternoon last week at about 10 p.m. The Sino-Korean Friendship Bridge and Dandong Station were completely closed off, according to the report.

“Starting at 10 p.m. Dandong Station was completely blocked, and two trains passed at an interval of about 20 to 40 minutes,” Daily NK’s source said. The source added the trains were headed to Shenyang, a major city in northeastern China.

UPI, in picking up the story, said other unusual movements, including the arrival of a North Korean military vessel near the Sino-Korean Friendship Bridge, occurred about four days ago, according to Daily NK’s source.

In 2011, when similar preparations were observed for Kim’s father’s visit to to China, Dandong Station was also completely blocked at the time and the Sino-Korean Friendship Bridge was closed off to the public.

Kim and President Donald Trump plan to hold a summit by late May. The international press has been buzzing with reports concerning behind-the-scenes diplomatic moves by various nations seeking to resolve the North Korean nuclear crisis.