A suspect is in custody related to an explosion that killed at least six people and injured at least 81 others in Istanbul on Sunday, Turkey’s interior ministry said, writes CNN.

The incident has been deemed a terrorist attack, Turkish Vice President Fuat Oktay said: “We consider it to be a terrorist act as a result of an attacker, whom we consider to be a woman, detonating the bomb”.

Turkish officials believe Kurdish separatists from the Kurdistan Worker’s Party (PKK) and the Democratic Union Party (PYD) were most likely behind the deadly suspected bomb attack, the country’s interior minister, Suleyman Soylu, told reporters Monday.

“It is PKK/PYD terrorist organization according to our preliminary findings”, - Soylu said in a press conference. He did not elaborate or provide details of how investigators had reached this conclusion.