ATHENS, Greece (AP) - Clashes broke out outside the Agriculture Ministry in central Athens Friday as thousands of farmers from across Greece headed to the Greek capital for a two-day protest against the government's plans to impose new tax hikes and reform the pension system.

ATHENS, Greece (AP) Clashes broke out outside the Agriculture Ministry in central Athens Friday as thousands of farmers from across Greece headed to the Greek capital for a two-day protest against the government's plans to impose new tax hikes and reform the pension system.

Farmers who arrived by ferry from the island of Crete earlier in the day rallied outside the ministry building, throwing tomatoes as tension escalated when police prevented them from staging a symbolic occupation of the ministry. Clashes soon broke out, with riot police using tear gas to repel protesters throwing rocks and setting rubbish dumpsters on fire.

Other protesting farmers from southern Greece were massing at a highway toll station near Corinth, with some vowing to drive tractors to Athens despite a government ban.

Bailout lenders are demanding that Greece scrap tax breaks for farmers and impose pension reforms that will lead to higher monthly contributions from the self-employed and salaried employees.

Farming associations have been staging highway blockades for more than two weeks against a planned overhaul of the country's troubled pension system, using tractors to block roads and forcing traffic into lengthy diversions.

The protests against the pension reform have united a disparate group of professions, including lawyers, artists, accountants, engineers, doctors, dentists, seamen and casino workers.