Washington, Nov 21: The United States has cautioned its citizens to defer non-essential travel to Turkey, warning new terror attacks could follow twin blasts aimed at British targets in Istanbul. In a travel warning, the State Department said yesterday's attacks and the strikes against two synagogues in Istanbul at the weekend, represented a significant change in the tactics of terror groups in Turkey.

"In light of the recent terrorist bombings, the Department of State recommends US citizens defer non-essential travel to Turkey," the department said. "The potential for violence and terrorist actions against US citizens and interests continues."

The warning said that it was unclear which groups had launched yesterday's attacks, though the top suspect is the al-Qaeda network.

"Terrorist actions may include, but are not limited to, suicide operations, hijackings, bombings, or kidnappings," the advisory said. "Terrorists do not distinguish between official and civilian targets."

Americans were advised to avoid public transport, residential areas, clubs, restaurants, places of worship, hotels, schools and resorts and beaches.

The advisory did however say that the US Embassy in Ankara and consulates in Istanbul, Adana, and Izmir remained open to provide services to American citizens.

The US government earlier suspended normal visa services at its consulate in Istanbul but kept it fully staffed for emergency assistance. Bureau Report