A female suicide bomber blew herself up inside a police station in Istanbul’s historic Sultanahmet district yesterday, killing one officer and wounding another, the city’s governor and Turkish media said.

The woman spoke English as she entered the building but her nationality and identity were unknown, Governor Vasip Sahin told reporters at the scene.

Turkish media said one of the officers died from his wounds.

There was no immediate claim of responsibility but the bombing comes less than a week after far-left group DHKP-C said it was behind a grenade attack on police near the Prime Minister’s office in Istanbul.

Police sealed off the street where yesterday’s attack happened, across the square from the Hagia Sophia museum and Blue Mosque and near the Basilica Cistern, which are among the top tourist destinations in one of the world’s most visited cities.

Public transport resumed after being briefly shut down and some tourists, braving heavy snow, were still walking around the historic Sultanahmet square.

The DHKP-C (Revolutionary People’s Liberation Party-Front) had warned of further strikes after last Thursday’s attack, in which a man carrying an automatic weapon was detained near the Ottoman-era Dolmabahce Palace.

The group was also behind a suicide bombing at the US Embassy last year as well as attacks on Turkish police stations.

Turkey faces other security threats.

Some of the thousands of foreign fighters who have joined the ranks of Islamic State militants in neighbouring Syria and Iraq have entered via Turkey, raising concern that they could return and strike on Turkish soil.

There have also been clashes in predominantly Kurdish southeastern Turkey in recent weeks between members of Kurdish Islamist party and youths linked to the outlawed Kurdistan Workers’ Party (PKK), which has also carried out urban attacks in the past.