Tensions have been rising in Gaza since Hamas's bloody seizure of power in June from Fatah forces of President Mahmoud Abbas. Immediately after Hamas's takeover, most rank-and-file Fatah supporters kept quiet for fear of retribution.
But with the Gaza economy in tatters and Hamas suffering from an international boycott, its leadership appears to be showing signs of strain while Fatah backers are slowly regaining confidence.
Despite its fundamentalist Islamic roots, Hamas this week banned public worship after Fatah supporters began holding prayer meetings that quickly turned into raucous protests against Hamas rule.
In a further challenge to Hamas's hold, Palestinian groups affiliated with the umbrella Palestine Liberation Organization, of which Hamas is not a member, called on members to strike tomorrow and demanded Hamas apologize for its actions and release protesters arrested yesterday. It would be the first general strike since the Hamas takeover, and the degree of observance will be an important barometer of opposition.
An explosive device thrown among protesters in the southern Gaza town of Khan Younis injured four people.
In northern Gaza's Jabaliya refugee camp, uniformed and plainclothes Hamas security forces beat several people and detained one man, witnesses said.