Protesters freed In Monday 's clashes , UN and Nato vehicles were set alight as hundreds of protesters gathered outside the court . Three UN policemen and two Nato K - For soldiers were injured in an explosion , thought to have been caused by a hand grenade . Several protesters have also been hurt . Earlier , some 100 UN police had arrested 53 Serbs in the operation to retake the UN court in a Serb - run part of the city .

Question: What happened to the troops during the detonation ?
Answer: They set their vehicles alight .None of the above choices .They gathered outside the court .They freed the protesters .