"SBU agents have established that a group of criminals from various regions of Ukraine has developed a program to secretly tap information from mobile devices. They sold their 'services' to customers through specially created websites. A customer, having filed a relevant application on such a website, first got a trial access to the 'service' by receiving a link which should have physically been 'uploaded' onto the phone of a person of interest," the report says.

According to the SBU, the program was activated automatically when the mobile phone was turned on; it did not show any signs of activity during work and acted disguised from the owner.

Read alsoThe Washington Post: Russian military was behind 'NotPetya' cyberattack in Ukraine, CIA concludes"The hacking software allowed the interception of telephone conversations, texting and multimedia messaging, detected a subscriber's whereabouts, recorded communication through popular messengers and e-mail, provided access to photo and video files stored on a mobile device. All received data was stored on a client's 'personal account' on the hackers' web resources. To use the 'service' on a permanent basis, the customer had to make payment for the required period through electronic payment systems," the SBU said.

SBU agents in Kharkiv region conducted a series of searches in the offices and houses of the criminal group's members and seized evidence of their illegal activities.

Specialists confirmed the exposed software is a special technical means of eavesdropping.

Criminal proceedings were opened under Part 2 of Article 359 (illegal use of special technical means of secretly receiving information) and Part 1 of Article 361 (unauthorized interference with electronic computers, automated systems, computer networks or telecommunications networks) of the Criminal Code of Ukraine.

The suspects are to be indicted. The investigation is under way.