The building of the military commandant's office in military unit No. 71717, Sertolovo, Leningrad region On the afternoon of February 17, the building of the military commandant’s office in a military unit in the city of Sertolovo, Leningrad Region, collapsed, killing three people. Information about other victims is being clarified. According to preliminary data, another person was injured. Eyewitnesses say there was an explosion. There is no official information about its reasons yet.