A massive explosion in south-eastern Turkey targeting a police headquarters in the city of Midyat, close to the country's border with Syria, has killed three and at least two members of the security services.

The Turkish Prime Minister Ahmet Davutoğlu said 30 were killed in the explosion as images shared on social media showed the police headquarters in Mardin province devastated by the blast.

Ambulances rushed to the scene in the majority Kurdish city just over 24 hours after 11 people were killed in a bombing in Istanbul which also targeted police.

Turkey has suffered a series of attacks from Islamist militants and Kurdish separatists in recent months. Islamic State (Isis) claimed two suicide bombings in tourist areas of Istanbul that killed 10 and four people in January and March respectively.

Kurdish militants usually favour military or police targets, although a splinter group of the Kurdistan Worker's Party (PKK), known as Kurdistan Freedom Hawks (TAK), was behind two recent bombings with high civilian casualties in Ankara.