A 10,000-strong crowd in Diyarbakir, the biggest city in the Kurdish-populated southeast, threw stones at police after attending a rally held by lawmakers from the now-defunct Democratic Society party (DTP).

Police were seen responding with tear gas and water cannon. At least 30 protestors were detained, security officials said.

Scuffles also broke out in the eastern town of Dogubeyazit where a group of protestors threw petrol bombs, fireworks and stones at police, Anatolia said.

Six people, among them five police officers, sustained light injuries, while nine demonstrators were taken into custody.

In the southern city of Adana, which is home to a sizeable Kurdish community, police used pepper gas against demonstrators armed with stones and petrol bombs, the agency said.

It was the fourth straight day of protests since the constitutional court banned the DTP on Friday for links with Kurdish rebels who have led a 25-year insurgency in the southeast.

There were also protests late Sunday in Istanbul -- which has a large number of Kurdish migrants -- with demonstrators attacking shops and vehicles, lighting bonfires and setting up barricades on the streets, Anatolia said.

Similar demonstrations were held in the southern city of Mersin and in Viransehir in the southeast.

The ban against the DTP undermined a government drive, launched in August, to expand the rights of Turkey's estimated 12 million Kurds more rights in the hope of ending the 25-year armed campaign by the outlawed Kurdistan Workers' Party (PKK) for self-rule.

The European Commission on Monday voiced fears that the ban could hit Turkey's democratic pluralism while underlining that the DTP's close links with PKK rebels were partly to blame.

"The decision of the constitutional court might deprive a significant segment of Turkish voters from political representation, a necessary condition for the successful outcome of the democratic opening," a spokesman for the European Union's executive branch said.

The DTP says it has "no organic links" with the PKK, but has refused to brand it a terrorist group.

The ban came atop already high tensions amid violent street protests over claims of worsening prison conditions for jailed PKK leader Andullah Ocalan and a rebel attack that left seven soldiers dead.