Thousands of opposition supporters filled the street outside Georgia’s national parliament building Sunday to protest municipal election results that gave the country’s ruling party a near sweep. 

Candidates of the Georgian Dream party won 19 of the 20 municipal elections in runoff votes on Saturday, including the mayoral offices in the country’s five largest cities: Tbilisi, Kutaisi, Rustavi, Batumi and Poti. 

The opposition alleges fraud.

Nika Melia, the head of the main opposition party United National Movement and a mayoral candidate in Tbilisi, claimed that “the victories gained by the opposition in many municipalities were taken away…like they never happened.”

An election observer mission of the Organization for Security and Cooperation in Europe said the “voting and counting were overall assessed positively despite some procedural issues, particularly during counting.”

“The persistent practice of representatives of observer organizations acting as party supporters, at times interfering with the process, and groups of individuals potentially influencing voters outside some polling stations were of concern,” the OSCE observers said in a statement.

Melia told the protest crowd, which shut down the capital’s main avenue, that opposition leaders would be sent to other cities to marshal supporters to come to Tbilisi for a massive rally on Nov. 7. 

The Saturday runoff elections were held after no candidate in the cities won an absolute majority during the first round of nationwide municipal elections on Oct. 2.

The elections were overshadowed by the arrest of former Georgian President Mikheil Saakashvili, the founder of the United National Movement, on Oct. 1.

Saakashvili left Georgia in 2013; he was convicted in absentia of abuse of power and sentenced to six years in prison. He returned to Georgia from his home in Ukraine, hoping to boost the opposition in the first round of voting, but was arrested within a day and imprisoned. He called a hunger strike soon after his arrest.