Pope Benedict XVI on Sunday denounced rocket attacks on Israeli border towns that provoked Israel's armed retaliation, and appealed in God's name for Jerusalem to use moderation and for Palestinian authorities to "neutralize" violent forces.

"The clashes among Palestinian factions in the Gaza Strip and the rocket attacks against inhabitants of the nearby Israeli cities, which prompted armed intervention, are provoking a bloody deterioration of the situation," Benedict told pilgrims in St. Peter's Square.

"Yet again, in the name of God, I beg that an end be put to this tragic violence, while I desire to express my solid closeness to the hard-put Palestinian and Israeli populations and assure them that I remember them in prayer," the pope said in his weekly appearance to the public from his studio window.

Israeli warplanes sent missiles slamming into a car carrying Hamas militants and a load of weapons before dawn on Sunday in Gaza, then demolished arms factories belonging to two Palestinian militant groups, the army said, in widening reprisals against Gaza rocket squads.

In Jerusalem, Prime Minister Ehud Olmert threatened tougher action if the intensified rocket fire on Israeli border communities continued. The sixth straight day of airstrikes came as an uneasy truce between warring Palestinian factions set in.

"I appeal to the sense of responsibility of all the Palestinian authorities so that, in dialogue and with firmness, the difficult path toward understanding is undertaken again, neutralizing the violent ones," Benedict said. "I invite the Israeli government to moderation and exhort the international community to multiply efforts to favor resumption of negotiations."

He said the deteriorated situation was causing "dismay."

"May the Lord inspire and sustain those working for peace," Benedict said.

Benedict — like his predecessor, John Paul II — has made repeated pleas for a negotiated end to the violence in the Middle East in hopes talks can bring about lasting peace, as the Vatican closely follows political and military developments in the Holy Land and the region.