Gaza's Hamas rulers on Sunday ordered census workers to halt the first Palestinian population count in a decade, derailing a rare joint endeavor with the rival Fatah movement. Hamas had agreed to cooperate with the census, which is being conducted by Palestinian Authority President Mahmoud Abbas' rival government in the West Bank. But Hamas officials on Sunday shut down the Gaza census office, saying the surveyors had violated an agreement to share their data with Hamas. "Data can't just be given to one side and not the other," said Mohammed Madhoun, an official in Gaza's Hamas government. "The government wants to make use of it for its future projects." Palestinians had said they hoped the first census since 1997 would help them in future peace talks with Israel.