Clashes between anti-government demonstrators and police are intensifying in the Armenian captial, where armed men have been holding hostages for four days and protesters erected barricades on a nearby avenue.

More than 50 people were injured in the clashes near a police station in Yerevan after police moved in late on Wednesday night to clear out the protest camp. Authorities said 51 people have been hospitalised, 28 of them police officers, and about 30 protesters have been detained.

The police station was seized on Sunday by a group of gunmen seeking the release of an opposition figure who was arrested in June for illegal weapons possession.

Roughly a dozen men, many veterans of Armenia’s 1988-1994 war with Azerbaijan, broke into the Erebuni district’s police station with a truck, taking several policemen hostage. One policeman, Colonel Artur Vanoian, was killed in the attack and two other people were wounded.

The group, led by Pavel Manukian, a mustachioed, rifle-toting, 50-something war veteran, called for the freedom of Zhirayr Sefilian, the leader of the anti-government Founding Parliament group. Sefilian was jailed in late June for allegedly plotting a government takeover.

The group also demanded freedom for another dozen suspected political prisoners, as well as the resignation of the president, Serzh Sargsyan.

Police have since blocked the entrance to the street leading to the police station, and brought in armored vehicles, special forces and, according to reports, snipers. Negotiations with the group, who call themselves the the Daredevils, are ongoing.

On Monday, three hostages were release but police say another five are still being held.

The protesters are sympathetic to the gunmen, and are blaming the government for the standoff.

“Those who stand by the government, and the government itself, call this a terror attack, but the actual terrorists are the current government,” said one man gathering with sympathisers near Yerevan’s Opera House. “They drove people to this condition.”

The Daredevils called for Armenians to take to the streets and overthrow the government, but the demonstrations have not yet attracted the numbers seen during the Electric Yerevan protests in 2015.

Last year there were mass demonstrations in the city, which saw people take to the streets for three weeks in June. The protests started as an objection to an increase in electricity tariffs and grew into more widespread criticism of the authoritarian government.

The largely peaceful demonstrations were eventually dispersed by police but succeeded in forcing concessions from the government.

This year’s standoff has deepened longstanding divisions in the country.

“We are doing this whether or not the people will join us … Let them live in this country, but we will not,” said Areg Kyureghian, an anti-government activist. .

Blogger Izabella Abgarian wrote that the government’s lack of response to previous rights abuses has prompted opponents to think that “issues are set to be resolved through arms”.

Sefilian’s supporters claim that he was arrested because of his group’s opposition to the government’s ceasefire with Azerbaijan after renewed fighting over the disputed Nagorno-Karabakh territory in April.

But the president, a former interior and defence minister, shows no sign of giving in to the gunmen’s demands to release the former Karabakh fighter. Sefilian, a wartime head of Karabakh’s armed forces, has not appeared in public since the standoff began.

Pro-government media and the National Security Service have described the attack on the police station as terrorism. They have compared the Daredevils’ actions with the 1999 gun attack on the Armenian parliament that killed the prime minister, Vazgen Sarkisian, and several other senior political figures.

But despite footage shown on Georgian television of a military aircraft flying over central Yerevan, many protesters believe that the government has no interest in a forceful response to the crisis as this would spark wider demonstrations.

MP Vahan Babaian, a member of the Prosperous Armenia Party, a sometime government ally, believes, said that the gunmen would be forced to surrender as they cannot survive indefinitely.

Writing on Facebook, he encouraged the security services to take note of those Armenians who support “the terrorists” on the social media site.

“They, as a matter of fact, live in our country,” he warned. “They walk among us and protect terrorist killers, justifying and making heroes of them.”

But human rights activist Artur Sakunts said the police station takeover was s not terrorism. “It is clear that, as a result of the armed group’s actions, the public is not terrified,” he said.