ATHENS, Greece - Thousands of Greek residents and business owners joined a strike and protested Wednesday on the Greek islands hardest hit by migration, demanding that the government ease severe overcrowding at refugee camps.

Most stores were closed and public services were halted on the islands of Lesbos, Chios, and Samos, where some refugee camps have more than 10 times the number of people they were built for. International aid officials have strongly criticized the living conditions at some Greek island camps.

The day of protest was organized by regional governors and mayors who plan to travel to Athens on Thursday to present their demands to the government. About 6,000 people joined a protest on Lesbos and another 2,000 demonstrated on Samos.

Nearly 75,000 people crossed illegally to European Union member Greece from Turkey in 2019, according to the U.N. refugee agency, an increase of nearly 50% from the previous year.

Island authorities are urging the Greek government to step up migrant transfers to the Greek mainland and want more information on its plans to build additional facilities to detain migrants listed for deportation.

While promising to take a tougher line on illegal migration, Greece’s six-month-old conservative government has been unable to deliver on promises to end the overcrowding at island refugee camps by building a larger network of camps on the mainland.

Officials at Greece’s largest refugee camp at Moria, on the island of Lesbos, are struggling to provide basic services to more than 19,000 refugees and migrants at a facility built to house fewer than 3,000 people. Most camp dwellers live in tents on a hill outside the fenced-off facility of container homes.

“What we want is for people to be transferred to the mainland in greater numbers, for the camp to be phased out and closed, and for any new facility to be located far away from populated areas,” Yiannis Mastroyiannis, the leader of Moria’s municipal council, told protesters at the main square on Lesbos. “The people in this area have suffered enough.”

While not joining the strike, Greek police and coast guard associations on the three islands issued statements in support of the protests. ___ Follow Gatopoulos at https://www.twitter.com/dgatopoulos