April 19 (UPI) -- North Korea is restricting access to a border river and banning people from using their mobile phones in places where they can still receive signals.
A source in North Hamgyong Province told Radio Free Asia the "vetting" of ordinary North Koreans has "made it difficult to even go outside."
"We must report to the head of the local cooperative every time we look for firewood or farm the fields," the source said.
North Koreans in North Hamgyong Province "who go to the mountains" are searched at sentry posts because people "can use their [international] mobile phones undetected" in more remote areas, according to the source.
North Koreans with relatives on the outside frequently use mobile phones that can access Chinese networks at the border.
A second source in North Hamgyong Province said "the center" has "completely banned residents from coming within 150 meters of the Tumen River."
The "center" refers to the central leadership in Pyongyang.
"People who used to do their laundry at the river, or use the water for everyday living are being inconvenienced," the source said.
The source also said water was supplied for about an hour morning and evening, but "recently even that source has been shut off."
"We now depend on mountain valley water merchants for our livelihoods," the source said.
North Korea has increased border surveillance, and China has also stepped up crackdowns on North Korean refugees.
In March, China may have arrested as many as 14 North Korean defectors, according to multiple sources.