Four men were arrested in South Korea for allegedly installing illegal cameras in motel rooms, then profiting from streaming the feeds to strangers online, police said.

Wireless cameras were placed in places such as cable boxes, power outlets and hair dryers across 42 rooms from 30 motels throughout ten cities in Yongnam and Chungchung provinces, according to a statement from the cyber bureau of South Korea's National Police Agency.

The cameras were allegedly streaming from November of last year until March 3.

Authorities only identified suspects as A, B, C, and D. Suspect A, 49, allegedly checked in to motels in order to install what police called "spy cameras."

After conspiring together in June last year, police said suspect A illegally set up the cameras "while Mr. B checked on whether the remote control was working."

Suspects A and B, 47, were arrested for violating sexual assault law and for distributing obscene material. Suspects C, 25, and D, 48, were arrested and released for being accomplices, according to police.

The men made about $6,800 by charging internet users $45 memberships to view the camera feeds.

"It is significant in it is the first time for the police to uncover spy camera crime that is live fed to an overseas site," police said.

South Korean authorities warned motel guests to pay special attention when staying in rooms. Police said they would "go to the very end for such a serious and grave crime that invades sensitive privacy of individuals."