Fatah prisoners held in Hamas jails in the Gaza Strip have gone on hunger strike in protest against their incarceration, Palestinian sources reported Sunday.The hunger strike is also in solidarity with hundreds of Palestinian prisoners in Israeli prisons who have also been refusing food for the past few weeks, the sources said.The Fatah-affiliated Palestine Press News Agency published a letter from the striking prisoners in the Gaza Strip in which they hold Hamas responsible for their continued imprisonment."We the prisoners in the shameful and despicable prisons belonging to the Hamas government declare our support for the heroic prisoners languishing behind Israeli bars," the inmates wrote in their letter."We have decided to go on hunger strike in solidarity with our brothers and call upon international institutions to put pressure on Hamas and the Israeli government to release all the prisoners."The prisoners in the Gaza Strip also appealed to Palestinians to exert pressure on Hamas to stop arresting Fatah supporters.Hamas has denied arresting Palestinians because of their political affiliations. Hamas spokesman said that all the prisoners are being held for their involvement in criminal activities and collaborating with Israel. Fatah officials say that at least 20 of their men are being held by Hamas without trial. Some Hamas prisoners held in Palestinian Authority prisons in the West Bank had also gone on hunger strike to protest against harsh conditions. Hamas says that the PA is holding dozens of its supporters in West Bank prisons.