Turkey's parliament approved the first clause of a bill to lift lawmakers' immunity from prosecution on Friday, a constitutional change that the pro-Kurdish opposition has warned could see its parliamentary presence all but wiped out.
In a secret ballot, 373 MPs in the 550-seat parliament backed the plan to lift MPs' immunity from prosecution, a high enough level of support to change the constitution directly without needing to hold a referendum.
The assembly was set to hold two further votes on elements of the bill on Friday which will determine the final outcome.
President Tayyip Erdogan has accused the pro-Kurdish HDP, parliament's third-biggest party, of being the political wing of Kurdish militants who have waged a three-decade insurgency in the country's largely Kurdish southeast. The HDP denies this.
Erdogan's opponents say the lifting of immunities is part of a strategy to push the HDP out of parliament, strengthen the ruling AK Party, and consolidate support in the assembly for the executive presidential system he has long desired.
HDP co-leader Selahattin Demirtas told Reuters this month that the lifting of immunities was likely to create more violence and stifle democratic politics.
Lawmakers currently enjoy immunity from prosecution. The new law will allow prosecutors to purse members of parliament who currently face investigation: 138 deputies, of whom 101 are from the HDP and main opposition Republican People's Party (CHP).
The HDP has said an overwhelming majority of its 59 deputies could be jailed, mostly for views they have expressed, virtually wiping out its parliamentary presence.