Berlin: Germany on Tuesday warned its citizens to avoid crowds and tourist sites in Istanbul after 10 people were killed and 15 wounded in a suspected terrorist attack in Turkey's largest city.
"Travellers in Istanbul are strongly urged to avoid for now large groups of people in public places as well as tourist attractions" and to stay informed via official travel advisories and the media, the foreign ministry said.
The ministry on its website warned of possible "political tensions as well as violent clashes and terrorist attacks across the country," adding that tourists should avoid large demonstrations.
It told AFP later that it could not be ruled out that German nationals were hurt in the Turkish attack and said crisis teams at the ministry in Berlin and the consulate in Istanbul were working to establish the facts.
The powerful blast rocked the Sultanahmet neighbourhood which is home to Istanbul's biggest concentration of monuments and is visited by tens of thousands of tourists every day.
Turkey has been on high alert after a series of attacks blamed on the Islamic State jihadist group including a double suicide bombing in the capital Ankara in October that left 103 people dead.