A car bomb blast near a police building in a Kurdish-majority province in southeastern Turkey has killed six people and injured at least 39 others, officials said.

The bomb attack, blamed by officials on the outlawed Kurdistan Workers Party (PKK), caused heavy damage to outer walls of the police headquarters in the town of Cinar in the province of Diyarbakir, Al Jazeera's Kadir Konuksever, reporting from Diyarbakir, said.

The fighters followed up the bombing with rocket attacks and gunfire, he said, adding that adjacent housing for families of police officers and a private house with civilians inside were also hit.

Three police relatives and three civilians, including two children, who were in the house near the blast, were killed in the incident, he said.

The PKK has been fighting against the Turkish state since 1984, initially for Kurdish independence, although it now presses for greater autonomy and rights for the country's largest ethnic minority. 

Turkish forces and PKK fighters have been engaged in intense clashes in the southeast of the country since a 2013 ceasefire collapsed in July and Turkey started an air campaign against the group.

The conflict has left tens of thousands dead over the years.

Source: Al Jazeera and agencies