Thousands of people took to the streets of Pristina, the capital of Kosovo, to protest against the EU's law enforcement mission Eulex, which was recently behind the arrest of Kosovar rebels for war crimes committed during the 1998-99 war of secession from Serbia.
Yesterday's protest was organised by several veteran organisations of the 1998-99 war and joined by an umbrella group of NGOs as well as students to "defend the honour of the KLA during the war".
The protesters marched carrying signs saying "Free the Freedom Fighters" and "Eulex go away", RFI reported.
Nine former rebels from the disbanded Kosovo Liberation Army (KLA) were arrested by Eulex police two weeks ago, on suspicion of killing and torturing ethnic Albanians and Serbs during the Kosovo war.
Among those arrested is a former Kosovo government minister.
Kosovo, a newly independent country which is not recognised by all EU member states (see 'Background'), is experiencing a major political crisis at a crucial time.
EU-sponsored talks between Belgrade and Pristina began recently, with the aim of giving the region more concrete European prospects.
On Monday, Kosovo's constitutional court ruled that the election of Behgjet Pacolli as president on 22 February was unconstitutional.
"The constitutional court reached a decision with a majority of its votes that the election procedure goes against Article 86 of the constitution, as well as against democratic principles," the court said.
According to Article 86, the president should be elected by a qualified majority of two thirds of all members of parliament. Additionally, there should be at least one other candidate for the position. Pacolli, a controversial multi-millionaire businessman, was elected with a simple majority of 61 votes.
It is not clear if there will be another election while Pacolli remains in the job, or if he must first resign, the BBC commented.
The ruling was the second against a Kosovo head of state in six months.
Fatmir Sejdiu resigned in September after the constitutional court said he had violated the constitution by also serving as a party leader.
Embarrassment for Brussels
The constitutional court's decision represents an embarrassment for the EU, which had rushed to welcome the results of the presidential election, despite opposition claims that undue pressure had been exerted on lawmakers in an attempt to tot up a majority.
"We respect the decision of the Constitutional Court and we will study the judgement as soon as it is published," EU foreign policy chief Catherine Ashton and EU Enlargement Commissioner Stefan Füle said in a joint statement, quoted by the Serbian press.
"We expect all sides now to work towards a solution in a constructive manner and according to the internal procedures," the two EU officials said on Tuesday (29 March).