ATHENS — Four people have been arrested on the Greek island of Lesbos after violence broke out during a protest against plans to build a new migrant camp, authorities said Tuesday.

Following a peaceful march to the site in heavy rain Monday, a small group of protesters set fire to earth-moving machinery being used by a contractor who has started work on the 87.5 million-euro ($100 million) project.

A police statement Tuesday said the four suspects face charges including attempted grievous bodily harm, arson and property destruction. It said another six people who allegedly participated in the violence have been identified.

The site at Plati, 30 kilometers (19 miles) north of the island’s capital, Mytilene, is due to be completed by September and house up to 3,000 migrants and asylum-seekers.

Lesbos was the busiest entry point into the European Union in 2015-16 when hundreds of thousands of refugees from wars in Syria, Iraq and elsewhere crossed westward from Turkey.

An acutely overcrowded refugee camp at Moria, further south on the island, was destroyed in 2020 by a fire — which Greek authorities say was lit intentionally by camp residents — and was replaced by temporary facilities.

The European Union is funding new camps being built on five Greek islands that face the Turkish coast. Freedom of movement is restricted at the new sites, drawing criticism from human rights groups.

Local authorities on Lesbos are backing the protests and have threatened to challenge the national Greek government in court to try to halt the project.