Voting is to end at 19:00 EET in Bulgaria as the country is holding local elections and a referendum on remote e-voting that, advocates say, is aimed at bringing expats and other citizens back into the political process.

Electoral officials have so far been unable to tell with certainty whether election day will be extended by an hour, a measure allowed where queues of voters are still there at closing hour.

The likely voter turnout at local elections is 46.5%, pollster Alpha Research annouced at 18:45.

For the referendum, results at 18:00 were estimated at 35.3%. 

If confirmed, turnout at the national referendum will be enough to make it valid and submit to Parliament the proposal it puts forward for consideration. 

Both polls, however, are being conducted amid uncertainty over how many voters took part.

The Central Electoral Commission added to the confusion, admitting its online database had suffered technical problems.

GERB and the BSP, Bulgaria's biggest parties (main ruling and opposition, respectively), announced, less than an hour before polls were to close, they would not hold traditional conferences

With nearly half of voters having cast a ballot by the afternoon, Sarnitsa, Bulgaria's "newest municipality" that was set up at the beginning of 2015, had the highest turnout in local elections - and also the lowest in the e-voting referendum.

Local electoral officials told the Bulgarian National Radio residents of Sarnitsa were not aware of the referendum's implications and refused to take part in the vote for that reason.

Claims of violations were submitted by citizens and political teams from all around the country, the most frequent ones being about campaigning, infringement of political rights, and breach of vote secrecy.

In the seaside resort town of Nesebar, a reporter for public broadcaster BNR showed images of ballots already cast in boxes which were folded in a way allowing electoral officials to track voters' preferences.