Yerevan, Armenia: Pro-opposition gunmen are holding four police hostage in the Armenian capital Yerevan, officials said Tuesday, two days after they seized a police building, killing one officer and taking several hostages.

‘Talks are underway with the hostage-takers. We are doing our best to resolve the situation without bloodshed,’ Armenia’s first deputy police chief Hunan Pogosyan told AFP.

Lines of police in flak jackets and helmets gathered outside the building Tuesday as parked trucks blocked off surrounding streets, an AFP photographer said.

The gunmen, who captured a large arsenal of police weapons, have so far refused to surrender.

They freed four hostages on Sunday and Monday, but were still holding four hostages as of Tuesday morning, Armenia’s national security service said.

The hostages include Armenia’s deputy police chief General Major Vardan Egiazaryan and Yerevan deputy police chief Colonel Valeri Osipyan.

The attackers have demanded the resignation of President Serzh Sarkisian and the release of detained opposition leader Zhirair Sefilyan.

More than 1,500 anti-government protesters rallied in Yerevan on Monday, calling for a peaceful resolution to the crisis.

Sefilyan — the leader of small opposition group the New Armenia Public Salvation Front — and six of his supporters were arrested in June after authorities said they were preparing to seize government buildings and telecoms facilities in Yerevan.

A fierce critic of the government, he was arrested in 2006 over calls for ‘a violent overthrow of the government’ and jailed for 18 months. He was released in 2008.

Last year, Sefilyan and several of his supporters were arrested again on suspicion of preparing a coup, but released shortly afterwards.

Sarkisian, a former military officer, has been president of the tiny country of 2.9 million people since winning a vote in 2008 that saw bloody clashes between police and supporters of the defeated opposition candidate in which 10 people died.