Thousands of Macedonian opposition supporters have joined nationwide protests against alleged police brutality — unrest that follows reports that the conservative government conducted a massive wiretap campaign.

Police on Friday blocked off streets leading to the government building in the capital, Skopje, where clashes during a protest Tuesday left 38 officers and one protester injured.

About 1,000 people were marching through the city late Friday. Local media said smaller demonstrations were being held in eight other cities.

The protests started Tuesday, after opposition leader Zoran Zaev — citing illegally recorded conversations — accused the government of trying to cover up the 2011 police killing of a 22-year-old man.

Zaev has accused Prime Minister Nikola Gruevski of tapping the phones of 20,000 people, including police, judges and journalists. Gruevski denies wrongdoing.