As North Korea continues its saber-rattling about nuclear strikes, we still know little about the country.
The North Korean government is notoriously secretive. Upon entering the country, visitors are instructed on what they can and cannot take pictures of. Customs agents inspect your mobile phone and other digital devices, including cameras, tablets, and storage cards, for banned content.
These restrictions prompted Getty photographer Xiaolu Chu to travel by train through the country in August 2015, documenting everyday life through his phone lens. He told Business Insider it was too risky to use a high-end camera because locals would report him to the police.
While some images were deleted during run-ins with the police, Chu shared some snapshots with us. Take a look at life inside North Korea.
Most Chinese tourists enter by train through Sinuiju or by plane through Pyongyang. He instead travelled to Russia so he could access the northern port at Tumangang.
The train ride from Tumangang to Pyongyang -- the capital of North Korea -- lasts a day. It was canceled because of a dispute between North Korea and South Korea.
When he later returned to the train station, he noticed portraits of the country's former leaders and the words 'long live' hanging overhead.
At night, these shrines were the only lit structures in the village. Other buildings sat in darkness.
A customs agent on board checked his tablet to make sure it wasn't GPS-enabled. The government also jams signals as a security measure.
The customs agent also checked his laptop and DSLR camera. Chu said the agent had no trouble operating the devices, with the exception of the MacBook.
The train chugged along, giving Chu glimpses of everyday life. This boy collected corn cobs beside the tracks.
Anytime the train pulled into a station, there were painful reminders of the country's poor living conditions. This little boy begged for money at a station in Hamhung.
Whenever he hopped out, Chu shot photos on his phone. 'DSLR is too obvious to take pictures in that condition as people in the village were extremely vigilant,' he said.
Several locals reported him to the police. 'A policeman and a solider stopped us and checked our mobile phone. I hid most of the pictures, (but a) few pictures were deleted,' he said.
The tourism bureau encourages visitors to take photos of student-exercise groups. These kids rehearsed for a celebration of the 70th anniversary of the Workers' Party of Korea.
Photography of anti-American protests is also welcomed. These students were marching against South Korea and the US.
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