Fatah called on Thursday for the release of a detained party-affiliated man held in a Hamas jail in Gaza, a party statement said.Fatah says Ramzi Kallab was arrested by Hamas security forces after returning from Egypt to the Gaza Strip.The statement accused Hamas of carrying out a campaign of politically motivated arrests against Fatah affiliates, a charge the Gaza government denies.The movement said the latest detention impeded efforts to implement a unity deal between the rival movements and called for the immediate release of all Fatah members held in Hamas\' jails.