Chaos swept into Macedonia's parliament Thursday night when protesters stormed the building and attacked lawmakers to protest the election of a new speaker despite a months-old deadlock in efforts to form a new government. Violence also swirled outside, with police firing stun grenades and clashing with demonstrators massed in front of the parliament building, and several people were injured. Authorities did not immediately confirm local television reports that up to 48 people had been hurt, including protesters and police officers. Many of the protesters were supporters of Prime Minister Nikola Gruevski, whose conservative party won elections in December but didn't get enough votes to form a government on its own. He has been struggling to put together a coalition government and his supporters have been holding nightly street rallies for two months across the country to protest the political situation. Dozens of protesters, some of them masked, initially broke through a police cordon after the opposition Social Democrats and parties representing Macedonia's ethnic Albanian minority voted to name a new parliament speaker. Shouting, hurling chairs and grabbing camera tripods abandoned by startled journalists, the protesters attacked lawmakers, including opposition leader Zoran Zaev, who was seen bleeding from the forehead. TV footage showed a bloodied Zaev and other Social Democrat lawmakers surrounded by protesters waving national flags, shouting 'traitors' and refusing to allow them to leave. A spokesman for one of the ethnic Albanian parties, the Democratic Union for Integration, told Telma TV that three other lawmakers were also injured. 'This is a sad day for Macedonia,' the spokesman, Artan Grubi, said. Police said lawmaker Ziadin Sela, who heads another ethnic Albanian party, was the most seriously injured and was taken to the emergency room of a Skopje clinic. Police said that about 10 officers were injured during the melee and that reinforcements had been sent to assist those inside the parliament building. After several hours of a tense standoff, with hundreds of protesters swarming through the parliament building, police said 30 lawmakers and a number of journalists who had been trapped inside had been safely evacuated. Television station Alsat M.TV in Albania broadcast a picture of Zaev leaving the building, his head heavily bandaged. Macedonian President Gjorge Ivanov went on television to appeal for calm and 'for reasonable and responsible behavior.' Speaking in a brief address to the nation, Ivanov said he had summoned the leaders of the country's main political parties for a meeting Friday. 'Lawmakers are primarily responsible for restoring the situation in accordance to the constitution and laws, which were violated today,' he said. Macedonia has been without a government since the elections. Coalition talks broke down over ethnic Albanian demands that Albanian be recognized as an official second language. One-fourth of Macedonia's population is ethnic Albanian. Amid the coalition negotiations, the Assembly of the Republic of Macedonia, as the Balkan nation's parliament is known, has been deadlocked for three weeks over electing a new speaker. Zaev, the opposition leader injured in the melee, suggested earlier in the day that a speaker could be elected outside normal procedures, an idea immediately rejected by the prime minister's party as an attempted coup. Zaev went ahead with the vote, and a majority in parliament elected Talat Xhaferi, a former defense minister and member of the Democratic Union for Integration. Protesters exploded in anger and fought their way into the building. Both the European Union and the United States condemned the violence and said they would work with the newly elected speaker. EU Enlargement Commissioner Johannes Hahn issued a joint statement with European Commission Vice President Federica Mogherini calling the violence 'wholly unacceptable' and urging calm and restraint. 'Democracy must run its course. We take positive note of the election of Talat Xhaferi as Speaker of the Parliament, as reported,' they said. The U.S. Embassy condemned the violence 'in the strongest terms,' saying in a statement that the assault 'is not consistent with democracy and is not an acceptable way to resolve differences.' The embassy noted that Xhaferi was elected by a majority of lawmakers. 'We will work with him to support democracy and to advance the interests of Macedonia,' it said. ___ Associated Press writers Llazar Semini in Tirana, Albania, and Derek Gatopoulos and Elena Becatoros in Athens, Greece, contributed to this report.