An Israeli aircraft has fired a missile at a target in the Gaza Strip.

Witnesses say an Israeli helicopter gunship fired the missile at a building housing the offices of an Islamic charity. The Israeli military says the attack targeted an office of a militant group in Gaza city. There were no reports of casualties.

The attack was the latest in a series of Israeli strikes that began Saturday after Palestinian militants in Gaza fired three rockets into southern Israel.

Earlier, Israel accused the Palestinian Authority of allowing wanted terrorists to cross into Gaza from Egypt in violation of the security agreement brokered by the United States last month.

Palestinian security officials admit some militants have crossed the border, but say Israel's demand that they be kept out is not part of the agreement.