THESSALONIKI, Greece (AP) — Clashes broke out overnight on Greece’s border with Turkey early Wednesday, after about 500 migrants attempted to break down a border fence and enter Greece.

Greek police said they used tear gas to repel the push to break down the fence south of the Kastanies border crossing. They said Turkish authorities also fired tear gas at the Greek border. The clashes began at 2 a.m. and lasted for roughly two hours.

An estimated 2,000 migrants are still camped out on the Greek-Turkish border, weeks after Turkey declared its borders to Europe open and encouraged migrants and refugees living in the country to try crossing into European Union member Greece.

Tens of thousands of people headed to the border despite Greece’s insistence that its eastern border, which is also the EU’s external border, was shut. The move came after months of threats by Turkish President Recep Tayyip Erdogan that he would open his borders and allow millions of refugees into Europe unless the EU provided more support for refugee care in Turkey.

The EU says it is adhering to a 2016 deal with Turkey under which it provides billions of euros in funds in return for Turkey caring for more than 3.5 million refugees from neighboring Syria.

The violence on the border came hours after Erdogan held a four-way video conference with the leaders of France, Germany and Britain to discuss the migrants crisis.

A statement from Erdogan’s office said the four leaders also discussed ways of resolving the Syria conflict and providing humanitarian aid in Syria’s troubled Idlib province. It didn’t immediately provide further details.

Tuesday’s teleconference between Erdogan, German Chancellor Angela Merkel, French President Emmanuel Macron and British Prime Minister Boris Johnson was arranged after the European leaders cancelled plans to travel to Istanbul over the coronavirus crisis.