"It was established that the culprits, through personal trusted connections, were searching for clients to provide 'services.' A former employee selected customers, whereas current employees technically ensured the reading of information," the report reads.
It notes that it cost $9,000 to wiretap one subscriber's phone for two months.
Investigators are currently establishing the exact number of subscribers who suffered from the actions of suspects involved in the case.
Criminal proceedings were launched under Part 3 of Article 368 of the Criminal Code of Ukraine.
The persons involved in the case have been detained and the decision is being made to declare them suspects in committing a criminal offense.
The operation to expose the culprits was conducted jointly with investigators of the State Bureau of Investigation, under the procedural control of the Chief Military Prosecutor's Office, the SBU said.