A protesting farmer walks next to parked tractors during a blockade in the northern Greek village of Promahonas village at the customs of the Greek-Bulgarian borderline on Monday, Jan. 25, 2016.

Greek authorities say more than 2,800 vehicles are trapped at crossings on the Greek-Bulgarian border, following road blockades by protesting Greek farmers and counter-protests by angry Bulgarian truckers.

Police say about 1,300 lorries and cars were stuck on the Greek side of the main Promahonas-Kulata crossing Thursday, and about 1,500 in Bulgaria. Scores more are waiting at another three border crossings.

Greek farmers have been manning highway blockades across Greece for weeks to protest a government-planned pension reform that will drastically increase their pension contributions.

Farmers had been allowing cars and buses through, and had been occasionally opening the border to lorries. But the Bulgarian truckers say farmers broke an agreement to occasionally let trucks through, and have been blocking their side since Wednesday.

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