JERUSALEM — Israeli naval commandos conducted a deadly raid on a flotilla of aid ships bound for Gaza on Monday, earning widespread condemnation and setting off a diplomatic crisis for the government of Prime Minister Benjamin Netanyahu.
Several European nations and Turkey summoned Israeli envoys for an explanation of the actions. At the request of Turkey, The United Nations Security Council met in emergency session on Monday over the attack, which occurred in international waters north of Gaza and killed at least 10 people. Mr. Netanyahu canceled his plans to meet with President Obama in Washington on Tuesday, an Israeli government official confirmed. Mr. Netanyahu, who is visiting Canada, planned to return home Monday to deal with fallout from the raid, the official said.
The White House, which had been at odds with the Israeli prime minister over settlements in East Jerusalem, released a statement saying that President Obama had spoken with Mr. Netanyahu and understood his need to return immediately to Israel. In addition to regrets about the loss of life, “the president also expressed the importance of learning all the facts and circumstances around this morning’s tragic events as soon as possible,” the statement said.
The criticism offered a propaganda coup to Israel’s foes, particularly Hamas, the militant group that holds sway in Gaza, and damaged Israel’s ties to Turkey, one of its most important Muslim partners and the unofficial sponsor of the convoy. As thousands of protesters took to the streets of Istanbul, Turkey recalled its ambassador to Israel, and Prime Minister Recep Tayyip Erdogan, calling the raid “state terrorism,” cut short a visit to Latin America to return home.
Mr. Netanyahu defended the Israeli military’s actions, saying the commandos were set upon by passengers on the ship and fired only in self-defense. The military released a video of the early moments of the raid that seemed to support his claim.
The Israeli Defense Forces said the naval personnel boarding the largest of the six ships in the aid convoy met with “live fire and light weaponry including knives and clubs.” The naval forces then “employed riot dispersal means, including live fire,” the military said in a statement.
Greta Berlin, a leader of the pro-Palestinian Free Gaza Movement, speaking by telephone from Cyprus, rejected the military’s version.
“That is a lie,” she said, adding that it was inconceivable that the civilian passengers on board would have been “waiting up to fire on the Israeli military, with all its might.”
“We never thought there would be any violence,” she said.
At least four Israeli soldiers were wounded in the operation, some from gunfire, according to the military. Television footage from the flotilla before communications were cut showed what appeared to be commandos sliding down ropes from helicopters onto one of the vessels in the flotilla, while Israeli high-speed naval vessels surrounded the convoy.
A military statement said two activists were later found with pistols they had taken from Israeli commandos. The activists, the military said, had apparently opened fire “as evident by the empty pistol magazines.”
The warships first intercepted the convoy of cargo and passenger boats shortly before midnight on Sunday, according to activists on one vessel. Israel had vowed not to let the flotilla reach the shores of Gaza.
Named the Freedom Flotilla and led by the Free Gaza Movement and a Turkish organization, Insani Yardim Vakfi, the convoy was the most ambitious attempt yet to break Israel’s three-year blockade of Gaza.
About 600 passengers were said to be aboard the vessels, including the 1976 Nobel Peace Prize laureate, Mairead Corrigan-Maguire of Northern Ireland.
“What we have seen this morning is a war crime,” said Saeb Erakat, the chief Palestinian negotiator for the government in the West Bank. “These were civilian ships carrying civilians and civilian goods — medicine, wheelchairs, food, construction materials.”
“What Israel does in Gaza is appalling,” he added. “No informed and decent human can say otherwise.”
At a news conference on Monday in Jerusalem, Israeli deputy foreign minister, Danny Ayalon, said the flotilla’s intent was “not to transfer humanitarian things to Gaza” but to break the Israeli blockade.
“This blockade is legal,” he said, “and aimed at preventing the infiltration of terror and terrorists into Gaza.”
Ms. Berlin, of the Free Gaza Movement, said, “They attacked us this morning in international waters. According to the coordinates, we were 70 miles off the Israeli coast.”
Within hours, diplomatic repercussions began to spread from the Mediterranean to Europe, where Catherine Ashton, the European Union’s high representative for foreign affairs, called for a full inquiry into the incident and the immediate lifting of the Israeli blockade.
A joint statement from Robert Serry and Filippo Grandi, two senior United Nations officials involved in the Middle East peace process and humanitarian aid to Gaza, condemned the raid, which they said was “apparently in international waters.”
“We wish to make clear that such tragedies are entirely avoidable if Israel heeds the repeated calls of the international community to end its counterproductive and unacceptable blockade of Gaza,” the officials said.
President Nicolas Sarkozy of France called Israel’s use of force “disproportionate,” while William Hague, the British foreign secretary, said he deplored the loss of life. Tony Blair, the representative of the so-called quartet of powers seeking a Middle East settlement, said in a statement that he expressed “deep regret and shock at the tragic loss of life.”