Demonstrators hold Palestinian flags during a protest against Israel at Taksim Square in Istanbul Monday ((Leonhard Foeger/Reuters) )

The UN Security Council was holding an emergency meeting Monday afternoon on Israel's deadly commando raid on ships taking humanitarian aid to the blockaded Gaza Strip, with the Palestinians and Arab nations calling for condemnation and an independent investigation.

Assistant Secretary-General Oscar Fernandez-Taranco said in his briefing to the UN's most powerful body that Monday's bloodshed would have been avoided "if repeated calls on Israel to end the counterproductive and unacceptable blockade of Gaza had been heeded."

Turkey's Foreign Minister Ahmet Davutoglu called the raid "murder conducted by a state" and demanded an immediate Israeli apology, an urgent inquiry, international legal action against the authorities and perpetrators responsible, and an end to the Gaza blockade."

Meanwhile, condemnation and protests spread across Europe and the Arab world Monday in reaction to the raid, in which at least nine pro-Palestinian activists, most of them Turks, were killed.

Reaction to the attack was a new blow to Israel's international standing at a time when the West, including the United States, has grown frustrated with its stance in the peace process.

Israel said the activists attacked its commandos as they boarded one of six ships taking tons of supplies to Gaza while the flotilla's organizers said the Israeli forces opened fire first.

The ships were in international waters of the Mediterranean Sea at the time.

The strongest reaction came from Turkey, the unofficial sponsor of the flotilla and previously a close ally of Israel. It recalled its ambassador to Israel and Turkish Deputy Prime Minister Bulent Arinc said it was cancelling three joint military drills and calling on the UN Security Council to convene an emergency session about Israel. Turkey is currently a member of the council.

Arinc said a Turkish youth soccer team currently in Israel would be brought home.

Governments in several countries demanded an explanation from Israel, which said its soldiers were trying to defend themselves against armed activists.

Turkey calls attack 'state terrorism'

The U.S. administration issued a cautious reaction, saying "the United States deeply regrets the loss of life and injuries sustained and is currently working to understand the circumstances surrounding this tragedy."

Prime Stephen Harper's office released statement saying that "Canada deeply regrets the loss of life."

Harper and Obama spoke by phone Monday afternoon, discussing the current situation in the Middle East as well as the upcoming G8 and G20 summits.

Turkish Prime Minister Recep Tayyip Erdogan said "it should be known that we are not going to remain silent in the face of this inhumane state terrorism."

In Istanbul, a crowd of about 10,000 tried to storm the Israeli Consulate. North of Jerusalem, Palestinians hurled bottles and stones at Israeli soldiers. In Jordan, hundreds urged their government to follow Turkey's lead and cut ties with Israel.

Dozens of Egyptians protested outside the Foreign Ministry in Cairo criticizing the Egyptian government and holding pictures of late president Gamal Abdel Nasser.

In Tehran, dozens of angry students pelted the UN offices with stones and eggs in protest, burning Israeli flags and chanting, "death to Israel" and "down with U.S." Police blocked them from reaching the building.

The president of Iran, a key supporter of Hamas, the militant group that controls Gaza, called the raid "an inhuman act." In Baghdad, an estimated 3,000 Shia followers of the anti-American cleric Muqtada al-Sadr shouted "Death, death to Israel!" and "Death, death to America!"

Demonstrations in France, Italy, Sweden

Riot police used tear gas to drive back hundreds of protesters demonstrating outside the Israeli Embassy in Paris. There were also demonstrations in Rome, Sweden, Norway, Cyprus and more than 20 cities in Greece.

In Athens, riot police used tear gas and stun grenades to disperse around 2,500 Greeks and Arabs protesting outside the Israeli Embassy. Some protesters threw stones and tried to push past police lines to reach the embassy. About 2,000 people demonstrated peacefully in Thessaloniki.

In Beirut, about 500 Palestinian and Lebanese activists protested in front of the local United Nations headquarters, setting Israeli flags on fire. In neighbouring Syria, more than 200 Syrian and Palestinian protesters staged a sit-in before UN offices.

The European Union's foreign affairs chief, Catherine Ashton, said the EU was deeply concerned and called on Israel to carry out an inquiry. British Foreign Secretary William Hague deplored the killings and called for an end to the Gaza blockade.

UN Secretary-General Ban Ki-moon condemned the violence.

Greece, Egypt, Sweden, Spain and Denmark summoned Israel's ambassadors demanding explanations for the violence, with Spain and France condemning what they called the disproportionate use of force.

Greece suspended a military exercise with Israel and postponed a visit by Israel's air force chief. Germany called for an immediate investigation but was careful not to directly place blame and said it was seeking information on six German citizens believed to have been aboard the ships.

The African Union issued a statement to "strongly condemn" the raid and said it "complicates the existing situation and the effort to bring just, lasting and comprehensive peace to the area."

Abdel-Rahman al-Attiya, the head of the Gulf Co-operation Council, a regional group, said "Israel is a renegade entity that violates international law" and said the attack should be considered "a war crime."

In Saudi Arabia, which has promoted a wider Arab-Israeli peace proposal calling for a land-for-peace swap, the cabinet, headed by King Abdullah, called on the international community to hold Israel responsible for its "barbaric" policies.