Turkey reviewing terror cell list
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ISTANBUL, Turkey (CNN) -- Turkey's security forces are discussing a list of about 1,000 people they fear could be involved in sleeper terror cells as Istanbul remains tense after a series of bombings.
The Turkish National Security Council was discussing the list Saturday as residents wondered if its biggest city would suffer more terror attacks.
Some on the list are Turkish but most of them are other nationalities who have had experience in countries such as Afghanistan, Chechnya and Bosnia.
Thirty people died in twin attacks on the UK Consulate and London-based HSBC bank in Istanbul Thursday. Earlier in the week 23 people were killed in a simultaneous strike on two synagogues.
Thousands of demonstrators took to the streets of Istanbul and Ankara Saturday in protest at the attacks. But union and non-governmental organizers criticized left-wingers of hijacking the marches.
Some banners read anti-U.S. and anti-Israeli messages.
Turkey's Prime Minister Recep Tayyip Erdogan said the terrorists would not defeat the country's fight for freedom.
At the funeral for Kerem Yilmazer, a stage actor killed outside the HSBC bank, Erdogan said: "Kerem was a symbol of a rebirth for peace and justice.
"The bombers won't silence our life in freedom, this life we have paid for dearly and will pay for again."
He also attended a memorial service for three Turkish policemen killed in Thursday's attack.
Erdogan said suicide bombers who attacked Jewish and British targets in Istanbul this week were Turkish citizens.
"Among our 57 citizens [killed at the blasts] there are unfortunately four of them who are the terrorists," he said. "It is them who have links outside Turkey, who did these acts."
Turkish officials are continuing to question a number of people arrested in connection with Thursday's attacks. (Full story)
Two more claims of responsibility have been for the bombing -- one from a person and one by a group, both claiming to represent Osama bin Laden's al Qaeda terrorist network.
In Washington, the U.S. State Department reissued its Worldwide Caution warning Americans they may be the targets of terrorist actions outside the United States.
It also, for the first time, mentioned al Qaeda specifically, instead of only talking about "terrorist groups."
"We are seeing increasing indications that al Qaeda is preparing to strike U.S. interests abroad. Al Qaeda and its associated organizations have struck in the Middle East in Riyadh, Saudi Arabia, and in Europe in Istanbul, Turkey," the caution said.
Jewish and Christian sites in Istanbul were given additional security, as was other high profile U.S. and British sites.
Israeli security sources, in an assessment of Saturday's synagogue bombings, said it is clear Turkey is a target because of its secular government and its ties to Europe, which terrorists are likely to target in the future.
Britain, the United States and Australia -- allies in the Iraq war -- have warned their citizens against non-essential visits to Turkey amid concerns of further attacks. (Warning of more attacks in Turkey)