As many as 4,000 supporters of former Foreign Minister Raffi Hovannisian, who finished second in Armenia's February 18 presidential election, demonstrated in the capital, Yerevan, on February 24.
The protest was not sanctioned by the authorities.
Some 8,000 Hovannisian supporters protested on February 22 in Yerevan, and smaller protests were held in other cities on February 23.
Hovannisian's Heritage party is calling for additional demonstrations in 21 cities between February 26 and 28, as well as another protest in Yerevan on February 28.
According to official results, incumbent President Serzh Sarkisian was reelected with 58.6 percent of the vote, while Hovannisian came in second with nearly 37 percent.
Based on reporting by Interfax and ITAR-TASS