Sawaf Abu Saif was in a "bad state," ARD Israel bureau chief Richard C. Schneider said, adding that more details would be provided on his overnight release later in the day.

Abu Saif was arrested Saturday in a Hamas crackdown on its rivals, including the moderate Fatah party of President Mahmoud Abbas.

On Wednesday, ARD closed its Gaza office to protest Abu Saif's detention.

The crackdown in the Hamas-controlled Gaza Strip followed a series of bombings in and around Gaza City Friday in which six people were killed and for which Hamas was blaming Fatah.

Hamas officials reportedly accused Abu Saif of being a Fatah sympathizer.