Updated

Several hundred Bulgarian nationalists have blocked the three main checkpoints at the Bulgarian-Turkish border to prevent what they called "electoral tourism" by Bulgarian citizens living permanently in Turkey.

The organizers from the nationalist United Patriots coalition claimed they had information that some 1,000 buses with at least 50,000 voters from Turkey were expected to cross the border ahead of Sunday's parliamentary elections.

The protesters claimed that Turkish officials were forcing expatriate voters to support a pro-Ankara party, which the nationalists consider a threat to Bulgarian national interests.

TV footage from the scene Tuesday showed protesters carrying Bulgarian flags and posters with the slogan "We are defending Bulgaria and Europe." Piles of car tires were placed on the road to stop traffic.