Anti-terrorism police detained at least 20 members of the opposition Peoples' Democratic Party (HDP) in Istanbul after the twin bomb attack on Saturday, according to a police source.
The suspects included HDP's Istanbul provincial head, Aysel Güzel, as well as district-level party heads, said the source, who spoke on condition of anonymity due to restrictions on talking to the media.
A total of 13 suspects have been arrested so far.
The arrests came after Saturday evening's deadly blasts in Istanbul that left 39 dead and 155 wounded. At around 10.30 p.m. (1930GMT), a car bomb went off outside a football stadium in the city's Beşiktaş district, two hours after the end of a Turkish league football match between Beşiktaş and Bursaspor. Seconds later, a second blast, a suicide bomb attack occurred in Maçka Park in the same neighborhood.
The suicide bomber blew himself up after police noticed him, according to the interior minister.
Police carried out simultaneous operations in Ankara, Adana, Manisa and Mersin
Anti-terror teams from Ankara Police Department raided in some specific spots in Ankara and detained 17 party members as part of an ongoing investigation. Among those detained are top HDP officials, including İbrahim Binici, the provincial head.
Simultaneously, about 500 police, backed by armored vehicles and a helicopter, launched an operation in the southern city of Adana and detained 25 HDP officials, around dawn
In another part of the anti-terror operations, 5 others from the party, including provincial heads were also detained in the western Turkish city of Manisa.
51 detained in Mersin
Meanwhile, Mersin Chief Public Prosecutor's office issued an arrest against the pro-PKK party's heads and members in the southern city of Mersin. Anti-terror teams detained 51 people accordingly early Monday.
Last month, 13 HDP lawmakers were arrested, and 10, including Co-Chairs Selahattin Demirtas and Figen Yuksekdag, remain in custody awaiting trial on terrorism-related charges.
The lawmakers face prosecution under anti-terrorism legislation after their parliamentary immunity was lifted earlier this year.
The government has accused the HDP of having links to the PKK, which is listed as a terrorist organization by Turkey, the U.S., and the EU.
