As reported by Censor.NET, this was announced by SBU's chief of staff Oleksandr Tkachuk on air of 112 Ukraine TV channel.
"Several minutes ago SBU officers apprehended Serhii Korsunskyi in the Poltava region; he is being transported to a pretrial investigation authority. He is reasonably suspected of participation in a terrorist organization, i.e. "Luhansk People's Republic," he noted.
Related materials: Anti-Terrorist Operation