Police said they were responding to a “threatening situation” when farmers, who were trying to get past a roadblock to cross a highway in the province of Friesland, began plowing their tractors into police officers and their vehicles. According to Friesland police, their shots hit a tractor, but no one was injured. Three suspects were arrested. Rijksrecherche, the Dutch government’s internal investigator, said it would look into the events since police had fired their weapons. A Friesland police spokesman did not respond to inquiries but said a statement would be released later Wednesday. Dutch farmers protested this week over government plans that could require farmers to use less fertilizer and reduce their livestock numbers, which could force some farms to close. The Dutch government wants to reduce nitrogen oxide and ammonia emissions, produced by livestock, by 2030. Cuts could reach 70 percent in some areas, according to the plans. In response, Dutch farmers have blocked supermarkets, distribution centers and roads in protests this week. On Wednesday morning they are expected to demonstrate at Elde Airport in Groningen, according to Dutch media. MP Caroline van der Plas has called for an “emergency discussion” with Dutch Prime Minister Mark Rutte and Justice and Security Minister Dilan Yeşilgöz-Zegerius about the escalating protests.