BERLIN, Oct. 29 (UPI) -- As the Turkish-Kurdish conflict threatens to escalate into a military invasion of northern Iraq, the violence has reached other countries in Europe.

Over the weekend tens of thousands of Turks and a smaller number of Kurds demonstrated in Western Europe.

Some 7,000 Turks from the Netherlands, Belgium and Germany took to the streets in the Dutch city of Utrecht; though windows were smashed, the demonstration remained largely peaceful, and police managed to keep the situation under control.

Yet in Brussels some 100 protesters of Turkish origin were arrested Sunday after an illegal demonstration ended in clashes with Belgian police.

In Berlin, a city home to an estimated 200,000 Turks, a protest against the Kurdistan Workers Party, known by its acronym PKK, on Sunday also turned violent.