Hundreds of Belgian police rounded up high-profile Kurds on March 4 as part of a Europe-wide investigation into alleged terrorist operations linked to the separatist Kurdistan Workers' Party (PKK).

Those arrested included ex-lawmakers, according to Turkish sources.

Police estimated that some 4,850 people from around Europe marched through central Brussels on Saturday carrying Kurdish flags and pictures of the rebel chief Abdullah Ocalan, who is in prison in Turkey.

Eight of those arrested, including two suspected PKK leaders in Europe, have been charged with taking part in the activities of a terrorist group, including recruiting young volunteers as PKK fighters, prosecutors said.

The demonstrators rejected the charges of terrorism and accused Belgium of acting under pressure from Turkey. They called for a political solution to the long-standing problems of Turkey's Kurdish minority.

The PKK is considered a terrorist group by Turkey, the European Union and the United States. It took up arms for an independent Kurdish state in 1984, sparking a conflict with Ankara that has claimed some 45,000 lives.