Security forces used tear gas and batons to repel anti-Israel protesters who tried to attack a U.S. consulate in Pakistan on Sunday, as tens of thousands in cities across Europe, the Middle East and Asia demonstrated against Israel's offensive in the Gaza Strip.

Israel launched its campaign in Gaza on Dec. 27 to stop rocket fire from the militant Palestinian group Hamas. Gaza health officials say nearly 870 Palestinians have been killed, roughly half of them civilians. Thirteen Israelis have also died.

Some 2,000 protesters in the Pakistani port city of Karachi burned U.S. flags and chanted anti-Israel slogans, and several hundred of them marched on the U.S. Consulate, senior police official Ameer Sheikh said.

"They were in a mood to attack," Sheikh said. "They were carrying bricks, stones and clubs."

A U.S. Embassy spokesman in Islamabad, Lou Fintor, said the protesters did not get close to the consulate, which was closed Sunday.

Washington provides a large amount of foreign aid to Israel as well as military and weapons assistance. Israeli military action is often perceived in the Muslim world as being financed and supported by the U.S. While Pakistan's government is a U.S. ally, anti-American sentiment is pervasive in the Muslim majority country.

In Spain, as many as 100,000 people attended rallies in Madrid and the southwestern city of Seville, urging Israel to "Stop the massacre in Gaza" and calling for peace initiatives. Spain's Foreign Minister Miguel Angel Moratinos will tour the Middle East starting Monday to promote solutions to the conflict.

An estimated 2,500 Lebanese and Palestinians meanwhile protested peacefully in downtown Beirut, waving Palestinian flags and calling on the international community to intervene in the Israeli attack.

A convoy of some 15 ambulances from an Islamic medical society sounded their sirens for 20 seconds in solidarity with Gaza medics. Leftist participants set fire to a large Israeli flag, while children taking part in the protest held bloody dolls representing Palestinian children killed in Gaza.

The death of children in the Gaza assault has become an enduring theme at protests.

Children carrying effigies of bloody babies headed a march attended by thousands in Brussels, Belgium. In the West Bank city of Ramallah, demonstrators held up dolls wrapped in red-stained shrouds and photographs of bloodied children.

Jewish communities appeared divided on the Israeli operations. In London, thousands of people gathered at Trafalgar Square to support the action in Gaza, while anti-Israeli protesters held a counter-demonstration nearby.

In a letter published in Britain's Observer newspaper Sunday, 11 leading British Jews urged Israel to end its Gaza campaign and negotiate a settlement for security reasons.

"We are concerned that rather than bringing security to Israel, a continued military offensive could strengthen extremists, destabilize the region and exacerbate tensions inside Israel with its one million Arab citizens," the letter said.

In Syria, as revolutionary songs blared from loudspeakers, demonstrators accused Arab leaders of being complicit in the Gaza assault. "Down, down with the Arab rulers, the collaborators," the crowd in Damascus shouted.

Separately, activists protesting the Israeli campaign were driving from Turkey to Syria in a convoy of 200 cars, and participants hoped Syrian protesters would join them at the border Monday, according to Nezir Dinler, an activist with the Istanbul-based Solidarity Foundation.

A few thousand people marched in largely peaceful pro-Palestinian rallies in the Italian cities of Rome, Naples and Verona. In Rome, municipal authorities were dispatched to erase graffiti — including Stars of David and swastikas — that had been scrawled on Jewish-owned stores and restaurants overnight.

Philippine policeman used shields to disperse Filipino student activists outside the U.S. Embassy in Manila to condemn the Israeli assault in Gaza. They held signs reading, "Stop U.S.-Israel Aggression against Palestine."

About 100 members of a leftist students' organization marched in Tokyo against the Israeli military action.