Turkish security forces take security measures at Sultanahmet square in Istanbul, Turkey on January 14, 2016. A blast at Istanbuls Sultanahmet tourist district on the morning of 12 January killed 10 people and wounded 15 others.Getty Images

It has been revealed that the suicide bomber behind the Istanbul bombing had left his fingerprints at an immigration centre on 5 January. Nabil Fadli, 28, who had no previous criminal record had entered Turkey from Syria and registered as a refugee, according to Turkish media reports.

"This individual was not somebody under surveillance. He entered Turkey normally, as a refugee, as someone looking for shelter," Prime Minister Ahmet Davutoglu told a news conference on 13 January. "After the attack his connections were unveiled. Among these links, apart from Daesh, we have the suspicion that there could be certain powers using Daesh."

So far only one person has been arrested in direct relation to the Istanbul bombings that resulted in the deaths of 10 German tourists and 15 others reported injured in the attack at the heart of Istanbul's historic district. Amongst the dead were mostly elderly people who were touring the city as part of a three-city tour run by Lebenslust (Lust for Life).

Turkey has welcomed nearly 2.2m refugees from Syria in its efforts to help Syrian people escaping the civil war. However, the country is often in the news due to its border being used by Islamic State (Isis) militants to cross over into Syria. The country is also a member of the US-led coalition in the war against (Dash). "It seems to make it less likely this was anything but a centrally commanded operation by the Islamic State," said Firas Abi-Ali, an analyst with the security consultancy IHS Country Risk, reported Yahoo News.

Meanwhile, the German interior minister, Thomas de Maiziere has said that there is "no reason" for Germans to change their travel plans to Turkey since, "it was an attack against humanity." However, German tour companies have offered their clients the choice to change their destination of travel with no added fee should they fear traveling to Turkey, reported The Telegraph.