In 2011, the FSB prevented 94 "crimes of a terrorist nature", including eight terrorist attacks. In particular, the agency foiled a planned suicide bombing in Moscow on New Year's Eve. However, the agency failed to prevent terrorists perpetrating the Domodedovo International Airport bombing. Over the years, FSB and affiliated state security organizations have killed all presidents of the separatist Chechen Republic of Ichkeria including Dzhokhar Dudaev, Zelimkhan Yandarbiev, Aslan Maskhadov, and Abdul-Khalim Saidullaev. Just before his death, Saidullaev claimed that the Russian government "treacherously" killed Maskhadov, after inviting him to "talks" and promising his security "at the highest level". During the Moscow theater hostage crisis and Beslan school hostage crisis, all hostage-takers were killed on the spot by FSB spetsnaz forces. Only one of the suspects, Nur-Pashi Kulayev, survived and was convicted later by the court. It is reported that more than 100 leaders of terrorist groups have been killed during 119 operations on North Caucasus during 2006. On 28 July 2006 the FSB presented a list of 17 terrorist organizations recognized by the Supreme Court of the Russian Federation, to "Rossiyskaya Gazeta" newspaper, which published the list that day. The list had been available previously, but only through individual request. Commenting on the list, Yuri Sapunov, head of anti-terrorism at the FSB, named three main criteria necessary for organizations to be listed.