Scuffles have broken out in the Turkish capital as police prevented pro-Kurdish politicians and other mourners from laying carnations at the site of two suspected suicide bombings that killed 95 people and wounded hundreds in Turkey's deadliest attack in years.

Turkey declared three days of mourning following Saturday's nearly simultaneous explosions that targeted a peace rally attended by activists, labor unions and members of the pro-Kurdish party.

The party's co-leaders, Selahattin Demirtas and Figen Yuksekdag, on Sunday planned to hold a memorial for the victims. They were held back by police who insisted investigators were still working at the site.

There was no immediate claim of responsibility for the attacks but Prime Minister Ahmet Davutoglu said Kurdish rebels and Islamic State militants were the most likely culprits.