In the first rally after their leader was released from the house arrest, activists linked to the main center-right Democratic Party defied the cold and rain to block traffic at five main intersections. The protesters accuse the left-wing government of Prime Minister Edi Rama of corruption, manipulating elections and usurping the powers of the judiciary.

Democratic Party leader Sali Berisha, 80, was released last month from house arrest imposed after he violated a court order. Berisha is charged with corruption.

“There is no election with Rama. With Rama there is only a battle for elections. Elections will never be boycotted,” said Berisha. “Our battle is unstoppable until his (Rama) overthrow,” he added.

Hundreds of police officers were deployed to protect government buildings and keep streets clear for traffic. After 90 minutes, the authorities began to push the protesters away from the intersections, which raised the tension and led to some clashes.

Earlier this year the conservative Democratic Party and its opposition coalition backers held protests over the arrests of Berisha and former President Ilir Meta in separate corruption cases, saying the charges are politically motivated.

The United States and the European Union have urged the opposition to resume dialogue with the government, saying violence won’t help the country integrate into the 27-nation EU.

Tirana has entered talks with the EU on alignment on issues including the rule of law, tackling corruption, security and defense. Albania aims to join the bloc by 2030, according to Rama.

Albania will hold parliamentary election on May 11 when voters living abroad will for the first time be able to cast ballots from overseas.

Post-communist elections in Albania have often been marred by irregularities, including vote-buying and the manipulation of ballot counts.