Detectives from the National Anti-Corruption Bureau of Ukraine (NABU) have finished their pretrial investigation of a criminal case involving nine individuals in the so-called "gas case."

NABU's press service on Friday said the case involves nine individuals who are not on the wanted list.

"Three of them are employees of the Public Joint-Stock Company Ukrgazvydobuvannia and six are representatives of joint venture operator companies controlled by Verkhovna Rada of Ukraine deputy Oleksandr Onyshchenko. He is suspected of organizing a corrupt scheme to steal money through the extraction of natural gas and sale under cooperation agreements with Ukrgazvydobuvannia. As a result, the state was bilked for some UAH 3 billion," the statement reads.

Ukraine's Security Service has opened its own investigation into the shenanigans after receiving information about possible state treason.

Suspects have open access to the results of the pretrial investigation.

As earlier reported, NABU detectives began their investigation in December 2015. They identified 27 suspects. Nine suspects have admitted their guilt and made plea bargains. Nine more suspects, including Onyshchenko, are on the wanted list.

Onyshchenko on August 8, 2016 was put in the national wanted list after Ukraine's parliament stripped him of immunity from prosecution. The issue of issuing an international arrest warrant is currently being processed.