Serbian nationalists shout slogans in front of the Croatian embassy during a protest marking the 20th anniversary of Croatia's four-day Operation Storm, in Belgrade, Serbia

Serbian nationalists shout slogans in front of the Croatian embassy during a protest marking the 20th anniversary of Croatia's four-day Operation Storm, in Belgrade, Serbia

Serbian nationalist leader Vojislav Seselj (C) and his party members burn the Croatian national flag in front of the Croatian embassy during a protest marking the 20th anniversary of Croatia's four-day Operation Storm, in Belgrade, Serbia

Serbian nationalist leader Vojislav Seselj (not seen) and his party members burn the Croatian national flag in front of Croatian embassy during a protest marking the 20th anniversary of Croatia's four-day Operation Storm, in Belgrade, Serbia