Head of the SBU Valentyn Nalyvaichenko announced at the extraordinary meeting of the National Security and Defense Council, Censor.NET reports.
He said that ATO forces discovered and exterminated 30 terrorists from a sabotage group involved in yesterday's Mariupol shelling.
Among them was a 40-year-old Russian citizen.
"We neutralized a terrorist, who was a citizen of the Russian Federation. His surname was Yemelyanov. His documents were also found and sent to Kyiv to officially announce... his Russian family where their son really is," Nalyvaichenko said.
He also said that the arrested terrorists' spotter whose surname is Kirsanov (call sign Haishnik) is a former employee of Ukrainian law enforcement agencies.
He has already been delivered to Kyiv and is giving testimony.
The shelling, according to the SBU, was organized by an associate of the leader of the DPR Alexander Zakharchenko called Ponomarenko, born 1977.
Nalivaychenko calls for the citizens to help in the arrest of the man.