HONG KONG — Two men have been arrested over the online streaming of the “intimate private activities” of 1,600 unsuspecting motel guests across South Korea, the latest instance of illicit electronic spying in a country where thousands of cases were reported last year.

The men — who are 48 and 50, but whose names were not released — are accused of setting up hidden cameras in 30 motels across 10 cities, the police said in a statement on Wednesday. The video was shown online for profit.

Tiny cameras with one-milimeter lenses were hidden in hair dryer holders, satellite boxes and closed electrical sockets, the police said. More than 800 intimate videos were then shown on a website that charged some viewers for a monthly subscription.

Overseas servers were used to conceal the camera users’ real IP address and evade detection. “This is the first time that livestreamed videos on overseas websites were detected” in a South Korean spycam case, the police said.