Thousands of people on Saturday marched down Istanbul's main central avenue to protest the twin suspected suicide bombing in the Turkish capital Ankara that killed at least 86 people.
The estimated crowd of 10,000 filled Istiklal Street in central Istanbul, with police maintaining a heavy presence but not intervening, an AFP photographer said.
Some carried placards reading "the state is a killer" and "we know the murderers", echoing allegations of state responsibility made in the aftermath of the attack but denied by the government.
Protests were also taking place in several other Turkish cities including Izmir on the Aegean and southeastern cities such as Batman and Diyarbakir, the Dogan news agency reported.
A protest earlier in Diyarbakir had ended with police using tear gas to disperse protesters.