The attackers mined the gym and the rest of the building with improvised explosive devices (IEDs), and surrounded it with tripwires. In a further bid to deter rescue attempts, they threatened to kill 50 hostages for every one of their own members killed by the police, and to kill 20 hostages for every gunman injured. They also threatened to blow up the school if government forces attacked. To avoid being overwhelmed by a gas attack like their comrades in the 2002 Moscow hostage crisis, insurgents quickly smashed the school's windows. The captors prevented hostages from eating and drinking (calling this a "hunger strike", which they said they joined too) until North Ossetia's President Alexander Dzasokhov would arrive to negotiate with them. However, the FSB set up their own crisis headquarters from which Dzasokhov was excluded, and threatened to arrest him if he tried to go to the school.