Farmers threw beets, sprayed manure at police and set hay alight in Brussels as hundreds of tractors sealed off streets close to the European Union headquarters, where agriculture ministers sought to ease a crisis that has led to months of protests across the 27-member bloc.

The farmers on Tuesday 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, police used tear gas and water cannon to keep the 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.

Several farmers, police and firefighters suffered injuries, but none was 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.

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 plan to better protect nature in the bloc and fight climate change was indefinitely postponed on Monday, underscoring how the protests have had a deep influence on politics.

EU member states on Tuesday gave their provisional approval 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 a change in EU policies under pressure from farmers is regrettable, warning that short-term concessions will come to haunt the bloc in a generation when climate change will hit the continent even harder.