North Korea is cracking down heavily on any form of social or political dissent since the recent ouster of eminence grise Jang Song-taek.

North Korean authorities are spreading word of the public executions of two of Jang's confidants, who were accused of "damaging the Workers Party" in a phrase that usually means corruption.

One source said scores of people across the country were publicly executed over the past month for offenses like selling and watching South Korean movies and TV series.

"The State Security Department issued a sudden decree in early October to eradicate 'impure' broadcast materials and that led to a widespread crackdown," the source said. "Fear is spreading across all provinces."

In Chongjin, North Hamgyong Province last month, North Korean authorities publicly executed around 40 prisoners in front of 15,000 spectators, while another five were executed on the spot at the orders of a people's court. In Hyesan, Ryanggang Province, two people were executed in October. Public executions also took place around the same time in four other provinces.