Investigators said on Saturday they had discovered the identities of those responsible for the January 24 bomb at a Moscow airport that killed 35 and injured dozens.
Investigation Committee head Vladimir Markin said details would be made public later. He did not clarify when.
Russia's Kommersant newspaper quoted on Thursday a police source as saying a Stavropol region resident, identified only as Razdobudko, was suspected of being involved in the attack.
But another police source told RIA Novosti on Friday that this information was incorrect.
No group has yet taken responsibility for the attack, which came less than 12 months after two female suicide bombers from the volatile North Caucasus struck the Moscow subway in a twin suicide bombing, killing 39 people.