RAMALLAH, West Bank ? Israel defied a U.N. Security Council demand Tuesday to end its six-day siege of Yasser Arafat’s devastated West Bank headquarters, and nine Palestinians were killed in an Israeli strike against alleged munitions factories and other targets in Gaza City.

Israel’s siege drew criticism from President Bush and many Israelis who questioned the wisdom of a military operation that may have boosted the Palestinian leader’s popularity at a time when voices had begun to be heard urging him to share power.

Sporadic pro-Arafat demonstrations persisted Tuesday despite curfews imposed in the West Bank in an effort to halt suicide attacks.

With the United States abstaining, the Security Council demanded early Tuesday that Israel end its operations, “including the destruction of Palestinian civilian and security infrastructure.” The resolution also called on the Palestinian Authority to ensure “those responsible for terrorist acts are brought to justice.”

In Washington, Bush said: “We’ve got to end the suffering. I thought the actions the Israelis took were not helpful in terms of the establishment and development of the institutions necessary for a Palestinian state to emerge.”