North Korea from the Yalu river

Fishermen prepare their nets on the North Korean side of the Yalu river across from the Chinese border town of Hekou Photograph: Ng Han Guan/AP

A North Korean waves from a bridge destroyed during the Korean war across the Yalu river in North Korea Photograph: Peter Parks/AFP/Getty Images

North Korean soldiers walk along the banks of the Yalu river near the town of Sinuiju Photograph: Reuters

Chinese tourists view North Korea from a boat on the Yalu river Photograph: Peter Parks/AFP/Getty Images

A North Korean soldier points as he is photographed from the Chinese border side of the Yalu river in northeast China's Liaoning province Photograph: Peter Parks/AFP/Getty Images

Farmers till the land in the North Korean hillside across from the Chinese border town of Hekou, in northeastern China's Liaoning province Photograph: Ng Han Guan/AP

A solitary tree towers on a hill along the North Korean banks of the Yalu river Photograph: Ng Han Guan/AP

Disused fishing boats rest behind a barbed wire fence that separates China and North Korea Photograph: Peter Parks/AFP/Getty Images

North Korean dock workers react to a passing Chinese tour boat along the Yalu river dividing China and North Korea Photograph: Ng Han Guan/AP

North Korean soldiers march along the border fence on the North Korean side bordering China near Dandong, northeastern China's Liaoning province Photograph: Ng Han Guan/AP

Chinese tourists use telescopes to look across the border to North Korea on 'Broken Bridge' over the Yalu river in Dandong. The bridge used to connect China and North Korea before it was bombed by the US during the Korean war and is now a tourist attraction Photograph: Peter Parks/AFP/Getty Images

North Korean workers unload what can be described as e-waste on the dockside of the North Korean town of Sinuiju, opposite the Chinese border city of Dandong Photograph: Peter Parks/AFP/Getty Images

A mother and daughter have their photo taken in traditional Korean dress on the banks of the Yalu river which separates China and North Korea in Dandong Photograph: Peter Parks/AFP/Getty Images

North Koreans wave at a passing Chinese tour boat cruising along the Yalu river Photograph: Ng Han Guan/AP

Chinese tourists on board a tour boat cruising along the Yalu river pass under the bridges linking North Korea with China in Dandong Photograph: Ng Han Guan/AP

Chinese students shoot water cannons towards the North Korean border across the Yalu river in Dandong, northeastern China Photograph: Ng Han Guan/AP

North Korean soldiers ride a motorcycle and side-car, seen from the Chinese border side of the Yalu river Photograph: Peter Parks/AFP/Getty Images

Two North Korean women wash their hair in the Yalu river on the border of northeast China's Liaoning province Photograph: Peter Parks/AFP/Getty Images

North Koreans work in a field behind a barbed wire fence which separates China and North Korea on the outskirts of Dandong in northeast China's Liaoning province Photograph: Peter Parks/AFP/Getty Images