The former prime minister of Kosovo left Tuesday for The Hague to be questioned by a special court investigating alleged war crimes by members of the separatist Kosovo Liberation Army two decades ago.

Ramush Haradinaj resigned as prime minister a week ago so as "not to be questioned as the country's leader" by the Kosovo Specialist Chambers, which is looking into crimes against ethnic Serbs allegedly committed during and after Kosovo's 1998-99 war.

"Today, as Ramush Haradinaj, as a citizen of Kosovo, I travel to the Hague for the third time, to prove that the Freedom Soldiers of Kosovo were always aligned with justice & the righteous cause!," Haradinaj tweeted.

At the time of the war, Kosovo was a Serbian province and Haradinaj was a top commander for the Kosovo Liberation Army. A former parliamentary speaker, a presidential adviser and other former KLA commanders also are expected to be questioned this week by the special tribunal.

The court, which is part of the Kosovo judicial system despite being based in the Netherlands, started questioning former Kosovo fighters this year.

Haradinaj was prosecuted for alleged war crimes and acquitted twice before. A United Nations tribunal first cleared him of war crimes and crimes against humanity charges in 2008. The appeals chamber of the International Criminal Tribunal for the Former Yugoslavia concluded in 2010 that witnesses had been intimidated. It sent the case back for a partial retrial. Haradinaj and two other former KLA commanders were acquitted in November 2012.