BELGRADE, Serbia (AP) — Thousands of people in Serbia’s capital rallied Saturday outside a pro-government TV station that protesters say promotes a culture of violence and should be stripped of its broadcasting licence after two mass shootings stunned the Balkan nation.

The protest started outside the Serbian parliament building before thousands marched toward the Pink TV building located in a residential area of Belgrade that also hosts foreign embassies and residences. The protesters booed loudly in front of the station’s offices, chanted slogans against populist leader Aleksandar Vucic and his government, and threw toilet paper rolls at the building.

“This is a factory of evil that has been spewing poison for years,” said opposition politician Radomir Lazovic.

Serbia’s populist authorities have rejected any responsibility for the May attacks. The president’s opponents, however, say hate speech and intolerance fueled by pro-government media and officials have helped foster violence in a society still reeling after a series of wars in the 1990s.

Protesters have called for measures to be taken against Pink TV and another commercial broadcaster, as well as pro-government tabloids, after the shootings on May 3 to 4 that left 18 people dead and 20 injured, many of them children.

The anti-government protesters also have demanded the ouster of key security officials and a media monitoring body during the street demonstrations — the biggest in years against Vucic and his government.

Vucic, a former ultranationalist who now says he wants Serbia to join the European Union but who has faced accusations of imposing increasingly autocratic rule, has dismissed the demands. Vucic has accused opposition leaders behind the rallies of exploiting the shooting tragedies to target him.

The shootings in May shocked Serbia, particularly because the first one happened in a Belgrade elementary school when a teenager used his father’s gun to open fire on his classmates. A day later a 20-year-old shot randomly at people in a rural area south of Belgrade.

Critics have cited Pink TV’s reality shows, with their violent scenes and appearances by crime figures and convicted war criminals as being among the reasons why the TV station should lose its national broadcasting permit.

Dozens of guards were deployed during Saturday’s protest outside the Pink TV building, which was covered in a huge Serbian flag. Smaller protests were also held Saturday in several towns and cities in other parts of Serbia following a blockade of the main north-south highway on Friday.