Federal Security Service
He is very close to the Russian president, so his visit could be some sort of precursor in case Putin decides to come to Belgrade himself this fall.
According to Sputnik, Zinichev will be met by Interior Minister Nebojsa Stefanovic, and will also visit the Serbian-Russian Humanitarian Center in Nis, where Russian experts train rescuers and firefighters from Serbia and the region.
Russian security services prevented a terrorist attack in St. Petersburg thanks to Turkey's help, Federal Security Service Director Alexander Bortnikov stated on April 4.
Federal Security Service (FSB) of Russia had seemingly arrested former military intelligence officer Sergei Viktorovich Skripal in 2004 for acting as an agent for the British intelligence service. Moscow claimed that he had revealed his identity to the British foreign intelligence service - MI6 - in exchange of pecuniary and other benefits.