Several thousand people have been protesting in the Armenian capital against rising electricity prices.
The protesters marched on June 22 from Yerevan's central Freedom Square toward the presidential palace, but were stopped on Baghramyan Avenue by riot police backed by water cannons.
At about 8 p.m. local time, the protesters sat on the road, blocking traffic.
Police said the protest march was "unlawful" and warned that they would disperse the rally.
Around midnight, police asked protesters to return to Freedom Square.
Authorities turned off the street lights, prompting protest coordinators to demand that they turn them back on.
Police later donned riot gear and announced they are ready to use force if protesters don't clear out in 10 minutes.
Earlier, President Serzh Sarkisian proposed to meet a small group of protesters if demonstrators stop the march, but the offer was rejected.
The civic group No To Plunder has been organizing around-the-clock protests in Liberty Square since June 19.
The Public Services Regulatory Commission of Armenia voted on June 17 to raise electricity prices by 16 percent to 49 drams ($0.1) per kilowatt hour (kWh). This was the third consecutive price hike in the past three years.
WATCH: Live Stream Of The Protest (natural sound)