Israel said Thursday its aircraft struck a Hamas military compound in the Gaza Strip overnight after balloons carrying firebombs and explosives were launched from the Palestinian territory.

Following the air strike, the Israeli military said two rockets were launched from the Gaza Strip toward Israel, setting off sirens in parts of the south.

It was not clear where the rockets landed or if there was damage.

The air strike hit targets within a compound for Hamas's armed wing in the northern Gaza Strip, the army and a Gaza security source said.

The security source said there was damage but no indication of casualties.

It was unclear if the firebombs and explosives that prompted the strike caused any damage inside Israel.

Palestinians in Israeli-besieged Gaza have frequently floated balloons fitted with firebombs over the border to damage Israeli property and have in the past succeeded in setting fire to large areas of farmland.

An ceasefire between Israel and Gaza's Islamist rulers Hamas brokered by Egypt and the United Nations had led to relative calm around Israel's April 9 general election.

But on Tuesday, Israel reduced the offshore fishing limit it imposes for vessels operating out of Gaza after a rocket was fired from the territory by Palestinian militants.

The rocket fell into the Mediterranean. The occupation army blamed its launch on Hamas ally Islamic Jihad.

Israel has fought three deadly wars against Palestinian in Gaza since 2008, leaving thousands of Palestinians killed and injured.

*This story has edited by Ahram Online