One more suspect has been taken into custody in connection with recent violent incidents in Turkey's southeastern province of Diyarbakır that left four people, including a conservative party member dead, authorities said Thursday.

The latest detention brings the total number of suspects in custody to 18, Diyarbakir Chief Public Prosecutor's office said.

On Tuesday, gunmen had shot dead a member of the conservative pro-Kurdish HÜDA-PAR member and chairman of Yeni İhya-Der charity, Aytaç Baran, just outside his office, in the province's Şehitlik town. Soon after, HÜDA-PAR supporters convened outside the office to protest the killing. The assassination was blamed on the Patriotic Revolutionary Youth Movement (YDG-H), an armed wing of the PKK and an adversary of HÜDA-PAR. Hours later, three more killings were reported. News agencies reported the victims were three men who are members of the pro-Kurdish People's Democratic Party (HDP).

Both the PKK and the HDP denied any connection to the killing of Baran. HDP Co-Chair Selahattin Demirtaş said "connections" between the killing of Baran and his party's members would only be revealed after an official investigation. He stressed that his party - that extols praise for jailed PKK leader Abdullah Öcalan and openly voices support for the PKK's actions - is not an armed organization.

Gunshots rang throughout Tuesday night in the city with rival groups clashing with each other. Two people were injured in the clashes. By Wednesday morning, hundreds of shops in the city were damaged after gunfire was sprayed through the streets. Tensions were palpable in the city and troops were deployed on the streets to assist the police for the first time since the Oct. 6-7 incidents last year that led to death of 50 people in the country.

Those incidents, which broke out in Diyarbakır and spread across the country, were a culmination of tensions between the PKK and HÜDA-PAR. Baran's friends said he was a "mentor" to Yasin Börü, a high school student who was among three men killed by a pro-PKK mob in Diyarbakır while they were delivering aid to poor families during the Oct. 6-7 incidents.

Related: Killing of Kurdish figure escalates tensions in Diyarbakır