ISTANBUL (AFP) - A Turkish court on Friday (Nov 4) placed the two co-leaders of the pro-Kurdish Peoples' Democratic Party (HDP) under arrest ahead of trial, the state-run Anadolu news agency said.

A court in the southeastern city of Diyarbakir ruled to remand Mr Selahattin Demirtas and Ms Figen Yuksekdag in custody after they were detained overnight as part of a terror investigation.

They would now be held in jail ahead of a trial, a date for which has yet to be set.

A total of 12 HDP MPs were rounded up overnight and in the morning in an unprecedented crackdown on the party that has caused international alarm.

Hearings were being conducted throughout the day by courts in Diyarbakir to decide whether to remand the deputies in custody.

As well as Mr Demirtas and Ms Yuksekdag, the head of the HDP's parliamentary faction, Mr Idris Baluken, and MPs Leyla Birlik and Nursel Aydogan were also placed under arrest by the courts.

However, lawmakers Ziya Pir and Imam Tascier were arrested under judicial control - the Turkish equivalent of bail - as was the prominent MP Sirri Sureyya Onder.