Israel Thursday closed its border crossings with Gaza Strip after Palestinian militants fired a rocket from the Hamas-ruled territory into southern Israel which violated a four-month-old ceasefire.

Israeli sources said a rocket landed Thursday in an open area near Israeli Sderot city, nearly one km away from northeast Gaza Strip.

A new group, calling itself the Palestinian Hezbollah after the Lebanese guerrilla, claimed responsibility for the attack, sources from Hamas administration said.

Following the incident, Israeli Defense Minister Ehud Barak consulted with his security chiefs and ordered the closure of Gaza commercial crossings.

In June, Egypt brokered a six-month ceasefire between Hamas and Israel with the goal of easing an Israeli blockade on the Hamas- ruled territory in exchange for calmness.

Israel gradually lifts the ban on goods into Gaza Strip and the ceasefire is holding despite several violations by Palestinian groups that oppose the deal.

Israel often closes the crossings for one day following every rocket attack.

(Xinhua News Agency October 30, 2008)