News1 reports that the Evangelical Baptist Church members accused of helping Yoo Byung-eun escape justice have been using Viber—an American application similar to KakaoTalk—to communicate with one another.

Because Viber’s servers are overseas, it’s hard for the authorities to bug them, and local investigators can’t conduct search and seizures.

Interestingly enough, Viber became famous in Korea because then-presidential candidate Ahn Cheol-soo—himself a cybersecurity expert—used it to communicate with his campaign folk, citing security.

The church folk are apparently changing their USIM cards, too.