Authorities block train station, bridge near North Korea border

March 26 (UPI) -- Large screens blocking views of Dandong Station have been installed, and local sources in the Chinese border city say there is speculation Kim Jong Un may have secretly paid a visit to China.

A China-based source told South Korean news service Daily NK the screens were installed a week ago, and police have been "conducting drills" with traffic barricades.

"Metal screens were placed at Dandong Station about a week ago, blocking views of any trains that cross the [Sino-Korean Friendship] Bridge," Daily NK's source said. "Since then there have been rumors [Kim Jong Un] made a stopover in China on his way to Russia."

The traffic barricade drills were held in the morning and afternoon of Sunday and around 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.

Other unusual movements, including the arrival of a North Korean military vessel near the Sino-Korean Friendship Bridge, occurred about four days ago, the source said.

Similar preparations were witnessed in 2011, when a train carrying former leader Kim Jong Il crossed the river, the source added.

Dandong Station was completely blocked at the time and the Sino-Korean Friendship Bridge was closed off to the public.

Commercial activity in Dandong has diminished following sanctions against North Korea, but with summits with South Korea and the United States planned for April and May, North Korea business activity is recovering, according to South Korean television network KBS.

A new North Korea trade delegation has been appointed to Dandong, and traders told KBS incoming North Korean orders for commercial products have been on the rise.