SKOPJE -- About 200 protesters have stormed into Macedonia's parliament building and beaten leading lawmakers after an alliance of Social Democrats and ethnic Albanian parties approved a new speaker of parliament.

RFE/RL's correspondents inside the parliament on April 27 saw protesters severely beat and bloody the face of Social Democratic Union leader Zoran Zaev, the head of a newly formed coalition that was asserting its right to govern by electing the new parliament speaker.

Three lawmakers from ethnic Albanian parties were also injured. With clashes occurring both inside and outside the building between police and protesters, in all 77 people were injured, including 22 police officers, the authorities said

Police said lawmaker Ziadin Sela, leader of the Albanian Alliance, was the most seriously injured and was taken to the emergency room of a Skopje clinic.

Zaev's party accused rival conservatives from the VMRO-DPMNE party of inciting the violence and causing "hatred and division" among Macedonians.

A spokesman for the party of the newly elected speaker called the outbreak of violence "a sad day for Macedonia."

Police outside the building fired stun grenades in an effort to disperse protesters and clear the way for the evacuation of lawmakers.

The demonstrators who stormed the building, some of them masked, threw chairs and pushed over camera tripods as they pounded legislators with their fists.

They appeared to be mostly from the conservative VMRO-DPMNE party that stands to lose its hold on parliament and the government with the emergence of the new governing coalition.

They had jumped over barriers with little resistance from outnumbered police at the start of their assault on parliament after news of the election of ethnic Albanian lawmaker Talat Xhaferi, of the Democratic Union for Integration, as parliamentary speaker.

U.S. and European leaders called for an end to the violence and for supporters of the VMRO-DPMNE to accept the result of the political process that led to the emergence of a new governing coalition.

"The acts of violence in the parliament are wholly unacceptable," EU foreign-policy chief Federica Mogherini said. "Democracy must run its course."

The U.S. Embassy in Macedonia said the assault "is not consistent with democracy and is not an acceptable way to resolve differences."

It indicated the United States was ready to recognize and work with the new speaker "to support democracy and to advance the interests of Macedonia."

RFE/RL correspondents report that the demonstrators damaged doors, stole the mobile phones and cameras of journalists, and advanced into a press room where Zaev and members of his coalition were conducting a press conference following Xhaferi's election as parliament speaker.

Blood could be seen streaming down Zaev's face as scuffles broke out between his supporters and VMRO-DPMNE supporters who stormed the building.

RFE/RL correspondents inside the parliament also came under attack along with other journalists there.

"The European Union is convinced that political dialogue in the institutions is the only way forward," Mogherini and EU Enlargement Commissioner Johannes Hahn said in a joint statement.

"We urge all political actors to honor the constitution of the country and act in the spirit of democratic principles, decency, and common sense."

The U.S. Embassy said the new speaker was elected legitimately despite months-long efforts by the VMRO-DPMNE to prevent that from occurring.

"A majority of MPs elected Talat Xhaferi as speaker of parliament during a regular, continued session of parliament witnessed by members of the public and press," the embassy said in a statement.

Albania’s Foreign Ministry said it was monitoring the "escalation" of violence in its neighbor, which it said was "unacceptable."

Macedonian President Gjorge Ivanov -- a VMRO-DPMNE leader -- summoned leaders from all parties for a meeting on April 28 and called for calm in an address on national television.

"I am calling for tensions to be calmed and for nonviolence," he said. "Lawmakers are primarily responsible for restoring the situation in accordance to the constitution and laws, which were violated today."

For a decade until last year, Macedonia was ruled by the VMRO-DPMNE and its leader, former Prime Minister Nikola Gruevski.

Demonstrators have taken to the streets of Skopje repeatedly during the past two months to protest against the emerging new governing coalition, saying the inclusion of ethnic Albanian parties is a threat to the country's national unity.

About a quarter of Macedonia’s population of 2.1 million people are of Albanian descent.

The VMRO-DPMNE -- which won elections in December but failed to build a majority coalition -- has for months successfully blocked Zaev from installing the new coalition he formed with ethnic Albanians based on a pledge to make Albanian the country's official second language.

Ivanov refused to give Zaev a mandate to form a new government, and the VMRO-DPMNE has employed obstruction tactics to keep the new coalition from asserting governance in parliament.

After the vote to make Xhaferi Macedonia's first ethnic Albanian speaker, VMRO-DPMNE lawmakers continued to object, challenging the legality of the vote, which they said was not carried out properly because the parliamentary session had formally ended.

With reporting by AP, AFP, and Reuters