Conditions in some Greek detention facilities are so poor they constitute "inhuman and degrading treatment," Greece's Ombudsman said in a report released Friday, which also noted continued overcrowding in about half of the country's prisons despite efforts to reduce the inmate population.

The watchdog's 2017 report noted particular problems at some police station and coast guard holding cells, with filthy conditions, insect infestations and no or limited access to an outdoor yard, natural light or washing facilities. Those affected included migrants awaiting deportation.

The Ombudsman visited the facilities unannounced in 2017 as part of Greece's commitments under the U.N.'s Optional Protocol to the Convention Against Torture.

Conditions in some facilities were described as "appalling."

Holding cells at the police station on the eastern Aegean island of Kos, where many asylum seekers initially enter Greece, were "entirely unsuitable to house even a small number of people," the report said, noting the 42 people being held when the Ombudsman visited in February 2017 was nearly double capacity, with some held there for several months.

"The conditions, due to the large number of detainees, were appalling. The areas were exceptionally dirty, and neither cleaning crews nor the police entered them," it said, adding that "the current conditions are judged with a simple visual (check) as inhumane and degrading."

Toilets in coast guard holding cells in the northwestern port town of Igoumenitsa "lacked any kind of appropriate hygiene conditions" and were apparently never cleaned, as no cleaners were hired nor were the detainees provided with cleaning materials.

Detainees in the men's cells slept on the floor using blankets as the cement beds provided had no mattresses, while underage detainees, who were held separately, had only a garden hose with cold water in a small outdoor yard to use for showers. Other detainees had to be transferred to the main coast guard building if they wanted to wash, the report said, noting it visited that facility in October 2017. "The detainees complained about insect bites, while the marks on their bodies were evident," it added.

Greek authorities have been making efforts to reduce overcrowding and improve conditions in migrant detention facilities as well as in prisons.

The Ombudsman recorded significant improvements in conditions in the country's once notoriously overcrowded prisons, with the total number of inmates just under 10,000. It noted, however, that almost half of prisons were operating at above 100 percent capacity, "with the evident danger" of the 10,000 people threshold being surpassed.