Dozens of furious protesters in northern Iran chanted slogans and threw rocks at police on Thursday, Iranian media reported, injuring five officers frustrated that their lush village had become a huge collection site for waste which they believe has become a health hazard.

Security forces dispersed the gathering and arrested several demonstrators, referring their cases to prosecutors in the town of Saravan, in the northern province of Gilan, the semi-official Fars news agency reported.

Saravan’s group of villagers have increasingly staged protests in recent weeks in an attempt to pressure authorities to find a solution to the rubbish that has been piling up in Saravan for four decades.

Footage circulating online this month showed protesters blocking garbage trucks from reaching the collection site. Authorities have long promised to open an incinerator in the area, but have yet to take action.

Saravan, with a population of 10,000, is located on one of the routes connecting the Iranian capital of Tehran to the bucolic tourist destinations of the Caspian Sea.

Iran has seen such protests in the past over the government’s handling of environmental issues like the country’s water crisis.