Over 1 million users have stopped using Korean mobile messengers amid allegations that authorities used them to monitor public opinion against the government, data showed Thursday.

The number of average users of local messengers dropped from 30.6 million in the third week of September to 28.9 million a week later, according to data provided by Rep. Jun Byung-hun of the main opposition New Politics Alliance and Democracy. Using data provided by online rank-tracking site Rankey.com, Jun found that the sharp drop had influenced most of the major services including Kakao Talk, Line and Nate-on.

The declining number of users appears to be a result of the prosecution’s announcement last month to step up monitoring of social media in a bid to clamp down on online rumors. The measure came on the coattails of President Park Geun-hye’s earlier statement the authorities must tighten their grip on the libelous rumors which “spark rifts within the society.”

What followed were serious of contentious measures that set off disputes over officials’ supposed attempt to muzzle the public opinion. People accused of spreading malicious rumors about Park were either slapped with legal charges or investigated. This included a Japanese journalist who published an opinion piece questioning her whereabouts during April’s deadly ferry accident, and even the article’s translator.

Amid the subsequent ruckus, local media and members of the opposition raised suspicion that members of the government agency have been listening in on private conversations that occurred via Kakao Talk, the country’s biggest mobile messenger. 

The prosecution denied the real-time monitoring, as did the messenger’s operator Daum Kakao. But the latter admitted Wednesday that it had provided content of mobile conversations of individuals for whom search warrants were issued.

Daum Kakao attempted to redeem itself by revealing its plan for a “privacy mode” that encrypts chat records to make it impossible for investigators to monitor the contents. But it remains to be seen whether its actions will be effective in regaining users’ trust.

Local media reported recently that a growing number of Koreans have gone into what was dubbed “cyberexile” to avoid prying eyes of the authorities to foreign-based messaging app such as Telegram.

“The ramifications of the recent events are not only confined to Kakao Talk. The underlying cause is the (public’s) mistrust toward government’s policy (on online monitoring),” said Rep. Jun.

By Yoon Min-sik (minsikyoon@heraldcorp.com)