The attack targeted a police station in the southeastern city and comes after Turkish authorities arrested senior HDP leaders from the region as part of a counter-terrorism investigation.
At least seven civilians and two police officers were killed when a car bomb targeting a police station exploded in Turkey's south-eastern city of Diyarbakir on Friday morning, Turkish Prime Minister Binali Yildirim said. The attack was originally attributed to PKK, which has been designated as a terror group by the US, EU, NATO and Turkey, but was later claimed by Daesh.
As of Saturday afternoon, the death toll has risen to 11, according to an unnamed police officer cited by Anadolu Agency.
The blast came hours after the Turkish government detained 11 lawmakers from opposition party HDP from several areas including Diyarbakir, Ankara, Hakkari, Van, Sirnak and Bingol.
"We as a nation strongly condemn this inhuman attack," Yildirim said, adding one suspected terrorist was also killed by the security forces.
The attack took place around 8am local time (0500 GMT) near a building used by riot police. Around 100 people were injured as the explosion occurred in a densely-populated area. Vehicles and nearby buildings were damaged by the impact.
Earlier in the day, the Diyarbakir provincial governor's office released a statement saying the PKK claimed responsibility for the attack. In a video message on a website associated with PKK, one of the group's commanders said it would intensify armed action against Turkey.
However, by early Saturday morning, Daesh had claimed responsibility for the attack through its news agency Amaq.
The Diyarbakir governor's office released another statement on Saturday evening saying, "We intercepted three radio transmissions between PKK terrorists indicating that the bombing was carried out by a PKK suicide bomber code-named 'Kemal' and three tonnes of explosives were used in the attack."
"Going by the information and the evidence we have, it is clear that this attack was carried out by the PKK," the statement added.
"The false information being shared on social media and some media channels regarding the suicide bombing, which resulted in a number of civilian casualties, is aimed at protecting the PKK."
HDP co-chairpersons Figen Yuksekdag and Selahattin Demirtas are among several HDP parliamentarians being investigated as part of an ongoing terror probe and for allegedly spreading anti-government propaganda. A twelfth lawmaker was arrested later in the day.
HDP currently holds 59 seats in Turkey's parliament as the third largest party. It won more than five million votes in the last general election. The HDP rose to success by emphasising minority, namely Kurdish, rights.
Turkey accuses the HDP of having links to the PKK, and of furthering the group's violent agenda.