RAMALLAH (Ma'an) -- Palestinian inmates in a southern Israeli jail are prolonging their mass hunger strike to protest their treatment by a special prison guard unit, a Palestinian Authority ministry said Thursday.

Palestinians held in Nafha prison joined a hunger strike throughout Israeli jails on Tuesday in solidarity with long-term strikers Ayman Sharawna and Samer Issawi.

The Nafha prisoners remained on hunger strike and refused to leave their cells on Wednesday and Thursday to protest prison guards raiding their cells during the strike, the ministry of prisoners affairs said.

Prisoners representative Alaa Abu Jazer complained about the raid to prison authorities, who told him the Yamar Dror unit -- responsible for narcotics searches -- had carried it out and were not under their command, according to the ministry.

Gamal Abu al-Hour, who was sentenced to five life terms and is affiliated to Hamas, was injured during the cell raids.