Inmates in 21 prisons across Greece have launched Monday a hunger strike to protest poor conditions in Greek jails and lengthy pre-trial detention periods.

According to reports, there are thousands of prisoners who are boycotting all food, as they protest overcrowding and demand better jail conditions, including proper medical care and restrictions on the time that detainees awaiting trial must spend behind bars.

"We are not suffering under the delusion that the ministry will accept all our demands; our goal is one small victory to bring a breath of fresh air into this oppressive situation," Panos Lambrou, the representative of the prisoners' support group, said as cited by DPA.

Greece's prisons are among the most overcrowded in Europe with 10,983 inmates crammed into jails designed to hold 7,543.