Palestinian-Canadians and their supporters held demonstrations in several cities Sunday in protest against Israeli air strikes aimed at security compounds in the Gaza Strip.

They rallied in downtown Montreal, Ottawa and Toronto.

Carrying flags and signs reading "Save Gaza," protesters gathered outside Ottawa City Hall, calling for an end to the violence.

Organizer Monzer Zimmo said international pressure from Canada and other countries is needed to stop the bloodshed.

Palestinian officials say 270 people were killed and as many as 700 wounded because of the air strikes. Israel launched the attacks Saturday in a bid to stop Hamas militants from firing rockets at Israeli communities.

On Sunday, Israeli aircraft dropped bombs on smuggling tunnels and Israel's cabinet authorized the military to call up 6,500 reserve soldiers for a possible ground invasion.

Retaliating for rockets

Israeli Foreign Minister Tzipi Livni said that in the days leading up to the missile strikes Hamas was firing 80 rockets a day into southern Israel. But there have been few deaths in the area, which has many bomb shelters.

On Saturday, a community leader who represents about 12,000 Palestinian-Canadians in the Mississauga, Ont., area called the military strikes "genocide ... a Hanukkah gift from the Israeli government."

"We have many of our community members, their background is from Gaza, and we cannot talk to them because they're still waiting to hear if they lost family members or not," said Farid Ayad, president of Palestine House.

Ayad said the Canadian government should push Israel to stop the siege and then send food and fuel to civilians.

Lawrence Cannon, Canada's minister of foreign affairs, issued a statement Saturday expressing concern about the escalating situation and loss of life and suffering on all sides.

"Israel has a clear right to defend itself against the continued rocket attacks by Palestinian militant groups which have deliberately targeted civilians," he said.

"First and foremost, those rocket attacks must stop. At the same time, we urge both sides to use all efforts to avoid civilian casualties and to create the conditions to allow safe and unhindered humanitarian access to those in need in Gaza."

Cannon also pushed for renewed efforts to reach a ceasefire between Hamas and Israel, and for Israeli and Palestinian leaders to remain committed to creating a peace deal.

Protests in Middle East, Europe

Elsewhere, thousands of protesters swept into the streets of cities across the Middle East on Sunday to denounce Israel's air assault.

From Lebanon to Iran, Israel's adversaries marshalled crowds out onto the streets for noisy demonstrations.

Turkey's prime minister, Recep Tayyip Erdogan, called the air attacks a "crime against humanity."

Some of Sunday's protests turned violent. A crowd of protesters in the northern Iraqi city of Mosul became a target for a suicide bomber on a bicycle. The bomber killed a 12-year-old boy and wounded 17 others.

In Beirut, police fired tear gas to stop dozens of demonstrators from reaching the Egyptian Embassy. Some in the crowd hurled stones at the embassy compound. It was unclear if anyone was hurt.

In London, police arrested half a dozen protesters who had scuffled with officers trying to clear a blocked road outside the Israeli Embassy in the city's Kensington neighbourhood.

Protests in Paris were peaceful. About 1,000 demonstrators turned out in the neighbourhood of Barbes, which has a large Arab population, and near the landmark Arc de Triomphe.

With files from the Canadian Press and the Associated Press