Eight people, including police officers, were killed and several others wounded in two separate bomb attacks in southeastern Turkey.

At least three people, including one police officer, were killed and 30 others wounded, including five police officers, when a handmade explosive was detonated by the Kurdistan Workers' Party (PKK) as a police vehicle was passing in the Kiziltepe district of the southeastern Mardin province on Wednesday, according to Transport Minister Ahmet Arslan.

The PKK, also on Wednesday, carried out a separate attack in the Sur district of the southeastern Diyarbakir province targeting another police vehicle, the government said.

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In Diyarbakir, five civilians were killed and 12 people, including five police officers, were wounded, according to Turkey's state-run Anadolu Agency.

A bomb-packed car was used in the attack, according to a statement by the provincial governor.

Earlier, officials said four soldiers had been killed and nine wounded when PKK fighters opened fire with rockets and long-range weapons from across the Iraqi border into Turkey's Sirnak province.

HDP offices raided

In a separate development, Turkish police said they arrested 17 people after "anti-terror raids" in at least 10 districts of Istanbul early on Thursday.

The suspects, accused of having links to the PKK or other pro-Kurdish groups, were charged with "being a member of a terrorist organisation, recruiting members for a terrorist organisation and organising illegal demonstrations," the state-funded Anadolu Agency reported.

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The headquarters of the pro-Kurdish Peoples' Democratic Party (HDP), in Istanbul's central Beyoglu district, was also raided as part of the police operation, according to Turkish media reports.

Several "organisational documents", one walkie-talkie and a jammer device were confiscated during the raid, Turkish newspaper Hurriyet reported.

President Recep Tayyip Erdogan and the ruling AK party have previously called for members of the HDP to be prosecuted, accusing them of being the PKK's political wing.

Turkey, the United States and the European Union call the PKK, an armed group that has been fighting for Kurdish autonomy since 1984, a "terrorist organisation".

The HDP, parliament's third-biggest party, denies direct links with the PKK and advocates for a negotiated end to the Kurdish conflict, which has claimed hundreds of lives since a peace process, once led by Erdogan and the AK party, collapsed in 2015.