Armenian prime minister Nikol Pashinyan said that there is an attempted military coup in the country. He has called on supporters to gather in Yerevan, adding that he prepares a televised address to the nation.
Armenian armed forces have earlier demanded the resignation of Pashinyan and his government in a statement on Thursday.
Yerevan has been seeing protests regularly since 10 November when Azerbaijani President Ilham Aliyev and Armenian Prime Minister Nikol Pashinyan signed an agreement on a ceasefire in Nagorno-Karabakh that was brokered by Russian President Vladimir Putin.
The deal ended the armed conflict which reignited in late September. Under the agreement, Baku regained control of the territories occupied by Armenians before the outbreak of hostilities, prompting a public outcry in Armenia.
Many Armenians interpreted it as a defeat in the Nagorno-Karabakh conflict.
Opposition parties have united behind calls for Pashinyan to step down, nominating former Prime Minister Vazgen Manukyan to head the government.