About 500 ( Russian estimate ) to 1,000 ( separatist claim ) rebel fighters remained in the city and more returned later with the civilians , often hiding in communication tunnels and basements of damaged buildings by day , and usually emerging by night to fire at Russian positions or to plant IEDs in the streets to attack patrols and vehicles the next day . In June 2000 , Russian police and special forces units began a major counter insurgency operation against the rebel forces in Grozny , but the bombings and clashes in the city continued as the guerrillas hid among the partially returned civilian population . According to the city 's mayor Bislan Gantamirov , the guerrillas were being helped by the Chechen police and the Russians were unlawfully killing up to 15 Chechens a day in Grozny . According to Russian military analyst Pavel Felgenhauer , one could " be robbed , raped or shot at any time – even if ... loyal to Russia " . In several incidents , helicopters were shot down by missiles over Grozny , killing a number of high-ranking military officials . In the deadliest attack , more than 120 soldiers were killed in the worst helicopter disaster in history . There was also a series of bomb attacks against local government buildings ( including suicide bombings ) . In 2002 , Grozny was struck by a truck bomb , which destroyed the seat of the pro-Moscow Chechen government , killing at least 83 . Military installations and police stations were also attacked and there were many daylight sniper shootings and other incidents , all aiming to kill or capture Russian soldiers venturing into the streets alone or in small groups
truck bomb
2002 Grozny truck bombing
Battle of Grozny (1999–2000)