Turkish legislators have scuffled for a second day in parliament over a new security bill which critics say aims to crush dissent.

Ruling and opposition parties' lawmakers traded punches and pushed each other during a late-night session on Wednesday. One opposition legislator fell down a set of stairs during the melee but was not hurt.

On Tuesday, five legislators were injured in a similar fight that saw chairs fly and deputies hit with a gavel.

The opposition parties meanwhile succeeded for a second time to hold up the start of the debate through tactics that included submitting motions on unrelated issues.

The government says the measures to give police heightened powers to break up demonstrations are aimed at preventing violence.