The Israeli army said that Palestinians fired a mortar bomb on a Jewish settlement in the Gaza Strip today, describing it as a "very serious incident."
Army spokesman Mr Olivier Rafowicz said the bomb damaged one house in the Netzarim settlement south of Gaza City but there were no casualties.
"For the first time since the beginning of the violence there was a Palestinian use of mortars against civilians," he told reporters. "It is a very grave and very serious incident."
The explosion was heard by Palestinians in Gaza City, who said it was followed by heavy machine-gunfire from Israeli tanks on Palestinian areas.
A Palestinian security source said the Palestinians had been informed by Israel of the mortar attack.
Earlier today, the armed wing of the militant Palestinian movement Hamas claimed responsibility for an attempted anti-Israeli attack overnight near Netzarim using a booby-trapped donkey cart.
Israeli gunfire detonated the cart that was loaded with explosives and left near Netzarim, a frequent trouble spot during the four-month wave of unrest in the Palestinian territories, in an explosion that killed the donkey.
AFP