The Turkish president has said that Israel's military raid on civilian aid ships bound for the Gaza Strip has caused "irreparable" damage to his country's relations with Israel, and will "never" be forgiven.

"From now on, Turkish-Israeli ties will never be the same. This incident has left an irreparable and deep scar," Abdullah Gul said in a televised speech on Thursday, as thousands gathered in the streets of Istanbul to pay their respects to the humanitarian activists killed during the raid.

South Africa has recalled its ambassador to Israel amid continuing diplomatic anger over Israel's deadly attack on humanitarian aid ships bound for Gaza.

The government had already condemned Monday's attack on the flotilla, which left nine civilians dead, as "a gross violation of international law".

Hundreds of activists deported from Israel after a failed attempt to breach the blockade on the Gaza strip have returned to Turkey. The activists received a warm reception on their pre-dawn arrival.
Around 1,000 people gathered at Istanbul's Ataturk airport to greet more than 500 returning activists. Thousands more celebrated and demonstrated against Israel in the heart of Istanbul.

The activists were greeted like heroes, and many could not wait to tell their stories to the waiting army of journalists.

"Twelve or 13 boats attacked us, along with four or five helicopters," one man said. " They just opened up fire on us. I heard the captain saying on the VHF radio we are unarmed."

Observers say such stories are fueling Turkish public outrage over Israel's seizing the six ships.

The flotilla aimed to break a blockade that Israel has imposed on the Gaza Strip in an effort to stop weapons from reaching the region that is controlled by the militant Hamas movement. The six ships had defied a warning from the Israeli navy not to approach the region, and the ships were boarded early Monday by Israeli forces.

Nine activists died during the operation. Their bodies also arrived in Turkey and autopsies of the dead said all died of gunshot wounds.

Israel says its troops only used their pistols after they were attacked, and released a video showing soldiers in riot gear descending from a helicopter into a crowd of men with sticks and clubs. Three or four activists overpowered each soldier as he landed, beating each one to the deck.

One of the main organizers of the relief effort was the Turkish charity the Foundation for Humanitarian Relief, which has Islamic roots. Israel accuses the charity of having links to terrorism, a charge it denies.

Turkish prosecutors are reportedly collecting statements for a possible case against Israel. The two countries have, until recently, had close political and military ties and Turkey was widely seen as Israel's only friend in the region.

Turkish Prime Minister Recep Tayyip Erdogan has held back from major diplomatic sanctions, other than recalling Turkey's ambassador. But Mr. Erdogan is facing increasing pressure to do more.

The Turkish Parliament passed a motion calling for a complete review of all political, economic and military ties with Israel. The country's powerful Islamic media, which traditionally supports the government, has called for severing ties.

Lawmakers in the Turkish parliament are urging the government to review political, economic and military ties with Israel in the wake of Israel's deadly raid on a Gaza-bound aid flotilla.

The lawmakers approved a declaration Wednesday that calls the raid a clear violation of United Nations rules as well as international law.

Earlier Wednesday, Turkish Foreign Minister Ahmet Davutoglu said his country wants an international commission set up to investigate the incident.

Turkey, which lost four citizens in the raid, has led the international outcry against the Israeli operation. Turkish officials have repeatedly called for an independent investigation, while the United States says it supports an internal probe done by Israel.

U.S. President Barack Obama spoke with Turkish Prime Minister Recep Tayyip Erdogan on the phone Tuesday. A White House statement said Mr. Obama expressed his condolences for Turkey's losses and stressed the importance of finding better ways to provide humanitarian aid to Gaza without undermining Israel's security.

Turkey has called for the Israeli blockade of the region to be lifted.

Nicaragua suspended its diplomatic relations with Israel on Tuesday in protest of the deadly raid.

Russia and the European Union issued a joint call Tuesday for an impartial probe, and separately condemned Israel's use of deadly force.

A White House spokesman, Robert Gibbs, said the Obama administration agrees with the wording of a U.N. Security Council statement, which does not specifically blame Israel for the bloodshed.

Israel has said its troops fired shots in self-defense after they boarded the aid convoy in international waters and encountered resistance.

Some information for this report was provided by AFP and AP.

U.N. Secretary-General Ban Ki-moon says he considering all the options for an investigation into an Israeli raid aboard a ship carrying humanitarian aid to the Gaza Strip that ended in the deaths of nine pro-Palestinian activists.

The U.N. chief stepped off a plane from Africa Wednesday and immediately went into separate meetings with ambassadors from Israel, Turkey, the Arab States and the permanent five Security Council member countries.

Afterwards, he told reporters he is ready to take "the necessary action" to start a full investigation into the events on the Turkish flagged ship the Mavi Marmara. But he said he would proceed in a deliberate manner, discussing it with all the concerned parties, before making a decision on how to go forward.

"It [the investigation] should be one which can gain credibility and support from the parties concerned," said Ban Ki-moon. "This is a very sensitive and even difficult, therefore, I am still in the process of these consultations. I will try to make it as impartial, as credible, as transparent as possible."

Mr. Ban added that there are "various options" for the investigation, but would not go into details.

He urged the Israeli authorities to quickly provide a full and detailed accounting of the events surrounding the incident, including information on those detained, wounded and killed.

He also noted the decision by the Geneva-based Human Rights Council to send an international fact finding mission to the region to look into possible violations of international law.

Secretary-General Ban said the violence aboard the Turkish ship could have been avoided if Israel had heeded earlier calls to lift its three-year long blockade which has prevented essential goods from reaching Gaza's 1.5 million residents.

"This tragedy only highlights the serious underlying problem," he said. "The long-running closure imposed on the Gaza Strip is counter-productive, unsustainable and wrong. It punishes innocent civilians. It must be lifted by the Israeli authorities immediately."

Turkey and Arab states are calling for an independent, international probe into the raid by Israeli commandos on the Mavi Marmara, which was in international waters when it was intercepted. Israel says its soldiers were acting in self-defense because passengers attacked them when the commandos repelled onto the ship from helicopters.

On Tuesday, the U.N. Security Council called for a "prompt, impartial, credible and transparent investigation" into the incident. Several council members said that meant an independent investigation with international elements, while the United States said Israel is capable of investigating itself.