"The team operated in the territory of our country for a long time," said Tkachuk.
"The leader of this sabotage and reconnaissance group is a citizen of Ukraine," the official said.
SBU spokesperson Olena Gitlyanska said that three Russians and four Ukrainians were among the detained members of subversive group, while another one, a citizen of Ukraine, was killed in a shootout during the raid.
Read alsoSBU slams sabotage group in special operation"Seven people have been arrested, the eighth one was killed," she said.
"The active phase of the special operation is continuing... When it is completed, we promise to provide comprehensive information on this group," Gitlyanska said.