A car bomb attack in the largest city in Turkey's mainly Kurdish southeast region killed eight people Friday, hours after authorities detained at least 12 pro-Kurdish legislators for questioning in terror-related probes.

Prime Minister Binali Yildirim said two police officers, a technician and five civilians died in the attack near a building used by the riot police. Up to 100 people were hurt in the blast but only seven of them remain in hospital, he said.

Yildirim also said one of the assailants was "caught dead" but did not provide details.

The Diyarbakir governor's office said the outlawed Kurdistan Workers' Party, or PKK, had claimed the attack, which the state-run Anadolu Agency said was carried out with a minibus laden with a ton of explosives.

The blast caused a large crater near the police building and damaged several buildings and businesses nearby. Television footage showed people walking among glass and other debris near buildings with windows blown out. Authorities imposed a temporary news blackout after the explosion, barring reports that could lead to public "fear, panic or chaos" and images showing the explosion and its aftermath.

Turkey has been plagued by a series of deadly bomb attacks in the past 18 months, carried out by Kurdish militants or Islamic State group extremists.

The PKK has waged a three-decade-long insurgency against the Turkish state and is considered a terror organization by Turkey and its allies. A fragile cease-fire collapsed in 2015 and at least 700 state security personnel and thousands of Kurdish militants have been killed since then, according to Anadolu.

Hours earlier, police detained 11 legislators from the pro-Kurdish People's Democratic Party, or HDP, including the party's two co-chairs, Selahattin Demirtas and Figen Yuksekdag. Prosecutors demanded that the two be formally arrested pending trial.

The detentions occurred in the middle of the night, with co-chair Demirtas describing on Twitter how he was taken into custody: "Police officials are at the door to my house in Diyarbakir with a detention warrant." State-run Anadolu Agency reported co-chair Yuksekdag was detained in her home in Ankara. Other senior officials taken away included Sirri Sureyya Onder and Idris Baluken. A twelfth legislator was also detained later during the day. One of the 12 was released on condition that he regularly report to authorities.

An Interior Ministry statement said a total of 15 detention warrants were issued by the chief public prosecutors in Diyarbakir and the provinces of Sirnak, Hakkari, Van and Bingol. Two of the legislators were determined to be abroad, and authorities are still searching for one.

The European Union's foreign policy chief, Federica Mogherini, expressed concern over the pro-Kurdish politicians' detentions on Twitter. She said the EU is in contact with authorities and she has called a meeting of EU ambassadors in Ankara.

Main opposition Republican People's Party Chair Kemal Kilicdaroglu denounced the detentions, "If you defend democracy, then you defend that those who came with elections should go with elections. Otherwise you'll butcher democracy in Turkey."

Yildirim responded: "If those who are elected but go hand in hand with terrorism, they of course need to be made to account."

Anadolu reported the lawmakers were detained for not appearing in court to testify in ongoing terrorism-related investigations.

The government accuses the HDP of being the political arm of the PKK, an accusation the party rejects.

President Recep Tayyip Erdogan and other senior government officials have repeatedly called for the prosecution of pro-Kurdish lawmakers on terrorism-related charges, which was made possible after legal immunities protecting legislators from prosecution were lifted in May.

Hundreds of charges were filed against HDP lawmakers following the lifting of immunity, including "disseminating terrorist propaganda" and "membership in an armed terrorist organization."

Demirtas reportedly reacted to the lifting of immunity by saying none of his fellow party members would voluntarily appear in court to testify. "If they want our testimony they'll have to force us there," he said, according to Anadolu.

Earlier this week Gultan Kisanak, the HDP mayor of the largest predominantly Kurdish city of Diyarbakir, along with co-mayor Firat Anli, was arrested over alleged membership in the PKK.

In September, the government similarly ousted 28 mayors and other administrators, mostly from the HDP, and appointed trustees in their place.

