Tens of thousands took to the streets of Bulgarian cities protesting against energy monopolies and high electricity prices. Protesters throwing eggs and stones clashed with police in Sofia as they approached the HQ of the regional power supplier.

Electricity bills have recently skyrocketed in Bulgaria, prompting thousands to join the wave of protests that have been sweeping the country since last week.

Sunday demonstrations saw people marching in more than 20 Bulgarian cities. Thousands of protesters demanded the country’s government to either re-nationalize power distribution companies, or resign.

Protests turned violent in the Bulgarian capital of Sofia, where police blocked the way to the headquarters of Chech-owned power supplier CEZ as the angry crowd of people armed with eggs, tomatoes and bottles approached. Protesters claim the police had stopped and beaten several people, including a young man and an elderly woman, according to the local media. Officials say the police were forced to retaliate after protesters started using pepper spray and tossing broken asphalt at them.

A demonstrator clashes with riot policemen during a protest in front of the headquarters of Czech power producer CEZ in downtown Sofia on February 17, 2013.(AFP Photo / Dimitak Dilkoff)

Government buildings were also pelted with various objects in Sofia, as the demonstrators demanded to stop the energy monopolies, chanted “mafia,” “monopolists out” and “resign” and carried banners reading “electricity + unemployment = genocide.”

“We cannot stand it anymore. My pension is 155 levs ($110) and my December bill was 175 levs. What should I do?”a protester told Reuters.

A protester holds a note reading "We will not pay" during a protest in front of Bulgarian Parliament building in Sofia on February 17, 2013.(AFP Photo / Dimitak Dilkoff)

The offices of power firms were attacked in several other Bulgarian cities during mass demonstrations. The seaside resort of Varna saw more than 5,000 people marching behind a coffin for electricity, heating and water monopolies, while burning their electricity bills. Thousands of others blocked the highway to Greece near the town of Dupnitsa.

The Sunday protests made one of the energy companies, CEZ, release statements offering their clients compensation. But speaking to the local Kanal 3 TV channel, CEZ chief Petr Baran only promised to make corrections“if there are mistakes” found in calculations.

Protestors clash with riot police during a demonstration in front of the headquarters of Czech power producer CEZ in downtown Sofia on February 17, 2013.(AFP Photo / Dimitak Dilkoff)

Such offers did not please Bulgarian protesters, who promised to return to the streets “every day” until their goals are met. But the government is not likely to give in, after the country’s Finance Minister Simeon Djankov has already ruled out the re-nationalization of power firms, telling the state channel BNT “There is no such possibility and I don't think any European Union member can afford to talk about nationalization.”

A member of the riot police holds up a baton as demonstrators clash with riot police during a protest in downtown Sofia on February 17, 2013.(AFP Photo / Dimitak Dilkoff)

People shout slogans as they block the traffic during a protest against high electricity bills in Sofia February 17, 2013.(Reuters / Tsvetelina Belutova)

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