BRUSSELS  After months of complaints by European dairy farmers angry over low prices, protesters in Brussels on Monday poured milk onto the streets, hurled eggs and other missiles, and started fires that filled the air with black smoke.

Police helicopters hovered overhead as hundreds of tractors  and some cattle  blockaded the area outside the European Union’s headquarters while agriculture ministers met in an emergency meeting.

The gathering of ministers, convened after pressure from France, failed to produce any breakthroughs apart from a decision to set up a committee to report on the dairy industry in June.

Monday’s protest was the latest by farmers who dumped around three million liters of milk on fields in Belgium last month.