24 people were held in Montenegro's parliament, 18 were MPs, after violence broke out following discussions over a controversial legislation on religious freedom.
One of the most sensitive clauses of the legislation is the requirement for religious groups to prove ownership of properties from before 1918, when Montenegro lost its independence and became part of a Serb-led Balkan kingdom.
Pro-Serb MPs hurled a firecracker, vandalized the building, threw plastic bottles and tried to assault other politicians when the amendments they proposed were rejected, according to the news agency AFP.
The altercation led to the detention of 24 people, including 18 lawmakers by the police. The bill was later passed in the early hours of Friday with 45 votes in favor.
All lawmakers, except three, were subsequently released. The ones kept in detention are suspected of attacking the speaker and stopping him from performing his duties, the state RTCG television said.
Shortly after midnight, while the assembly was in session, opposition leader Andrija Mandic said: "We are ready to die for our church and that's what we are demonstrating tonight."
Prime Minister Dusko Markovic condemned the violence on the floor of the parliament.
Montenegro witnessed nationwide demonstrations in recent weeks against the controversial law. (Credit: AP)
"Unfortunately, I have to express regret because of an irresponsible attitude towards the parliament and, of course, a topic that instigated lawmakers of the Democratic Front party to behave in such a way.
"I believe that Montenegro today, Montenegro in the 21st century, does not need such political behaviour in the Montenegro parliament," he added.
Montenegro witnessed nationwide demonstrations in recent weeks by supporters of the Serbian Orthodox Church (SPC) who claim that the new law would take away property from the church.
The SPC, which manages hundreds of monasteries in the country, fear that the authorities might use the law to seize its assets. The government has denied the suggestion.
In a statement, the church slammed the government for "inciting divisions and hatred," and pushing the country "into a situation that cannot bring any good to anyone."
"Thanks to this, the Orthodox Christian faithful in Montenegro are facing one of the saddest Christmases in recent history," it said.
The SPC remains the official Orthodox church in Montenegro with almost 72 percent of the country's population of 620,000 practising the faith.
A separate Montenegrin Orthodox Church declared its separation from the SPC in the mid-1990s but is yet win recognition from other Orthodox Christian churches.