Anti-terrorism police detained at least 37 members of the opposition Peoples’ Democratic Party (HDP) in two separate operations in Istanbul and Ankara early Monday morning, according to police sources.

Axar.az reports citing to Anadolu news agency.

Twenty members were detained in Istanbul, including HDP’s provincial head Aysel Guzel as well as district-level party heads, a police source, who spoke on condition of anonymity due to restrictions on talking to the media, said.

In a separate operation, 17 more HDP members, including the party's Ankara provincial head, Ibrahim Binici, and other district-level heads were also detained in the capital, another police source, who also spoke on condition of anonymity due to restrictions on talking to the media, said.