Farmers in central Greece on Sunday blocked a highway with tractors and poured cans of milk on the ground to protest against rising energy costs. Hundreds of tractors were parked on the major transport route outside the city of Larissa as part of the protest. The farmers were demanding the abolition of the electricity price adjustment clause, which the government said reflect changes in the price of oil and natural gas imports. Protesters were also calling for lower fuel taxes. Greek farmers say they are determined to shut down all the country's major highways if the government doesn't meet their demands.