LJUBLJANA, Slovenia (AP) — Police fired tear gas and water cannons at anti-government protesters in Slovenia’s capital on Tuesday, the eve of a major European Union summit.

Hundreds of protesters were opposed to the government’s tough anti-coronavirus measures in the small EU nation and this was the third such incident in Ljubljana within a month.

EU leaders have been gathering for a summit with Balkan officials on how to keep engaging with their Western Balkans neighbors. The 27-nation bloc’s once-successful enlargement policy faces an impasse.

The protest isn't directly linked with the EU summit, but protest leaders apparently sought the opportunity to get more media attention from reporters covering the event.

Slovenian police have placed checkpoints and limited traffic and movement in Ljubljana and at the venue where Wednesday's summit will take place a few miles away from the capital.

A leader of the protest has reportedly been detained and police stopped about 30 buses from bringing in the protesters from other Slovenian cities.

A police helicopter hovered over the capital’s downtown as police fired tear gas and water cannons as protesters tried to march through downtown Ljubljana.

Slovenian authorities have introduced tough requirements for the use of COVID-19 passes, including for going to work in all state-run firms. People must show that they are either fully vaccinated or that they have taken an expensive PCR test.

The protesters carried banners reading “Stop Corona Fascism” and demanded equal rights for both those who are vaccinated and those who are not.

Like much of Central and Eastern Europe, Slovenia in recent weeks has seen a rise in new coronavirus infections. The country of 2 million people has fully vaccinated nearly 48% of its population, a smaller share than in many other EU nations.

Slovenia currently chairs the EU presidency.