Farmers have thrown beets, sprayed manure at police and set hay alight as hundreds of tractors again sealed off streets close to the European Union headquarters.

The demonstration took place on Tuesday as agriculture ministers sought to ease a crisis that has led to months of protests across the 27-member bloc.

The farmers protested against what they see as excessive red tape and unfair trading practices as well as increased environmental measures and cheap imports from Ukraine.

“Let us make a living from our profession,” read one billboard on a tractor blocking a main thoroughfare littered with potatoes, eggs and manure.

As the protests turned violent again, police used tear gas and water cannon to keep farmers and some 250 tractors at bay, even as ministers met to push through measures meant to calm the crisis.

Authorities asked commuters to stay out of Brussels and work from home as much as possible.

Farmers, police and firefighters all had to nurse injuries, but none were life-threatening. The government lambasted the farmers for failing to contain violent elements that threw e-bikes off a bridge and set the entry to a subway station aflame.

Interior Minister Annelies Verlinden insisted the guilty would be prosecuted, adding: “The violence, arson and destruction during the protests are unacceptable.”

With protests taking place from Finland to Greece, Poland and Ireland, the farmers have already won concessions from EU and national authorities, from a loosening of controls on farms to a weakening of pesticide and environmental rules.

A major EU plan to better protect nature in the 27-nation bloc and fight climate change was indefinitely postponed on Monday, underlining how the protests have had a deep influence on politics.

Belgian farmer Yolin Targe said: “In order to have a strong Europe, there is a need for a strong agriculture. So we are here to remind them that their farmers should be a priority.

“We have to deal with a lot of administrative tasks. We have to deal with a lot of environmental restrictions. We are in favour of doing our best for the environment, but still, agriculture should be a priority.”

EU member states on Tuesday gave their provisional blessing to proposals that amount to weakening or cutting rules in areas like crop rotation, soil cover protection and tillage methods.

Small farmers, representing about two-thirds of the workforce and the most active in the protest movement, will be exempt from some controls and penalties.

The EU parliament is expected to decide on the proposals in late April.

Environmentalists and climate activists say the change in EU policies under pressure from farmers is regrettable. They say the short-term concessions will come to haunt the bloc in a generation when climate change will hit the continent even harder.

Politically, the bloc has moved to the right over the past year.

The plight of farmers has become a rallying cry for populists and conservatives who claim EU climate and farm policies are little more than bureaucratic bungling from elitist politicians who have lost any feeling for soil and land.