Turkey's prime minister says there are strong signs that two attacks at a peace rally in Ankara were suicide bombings.
Prime Minister Ahmet Davutoglu also declared a three-day official mourning for the 86 victims of the two explosions as well as for people killed in terror attacks since July.
The explosions occurred Saturday as hundreds of people were gathering for the peace rally by leftist and Kurdish activists.
The explosions in the Turkish capital of Ankara injured at least 186 people, the country's health minister said.
The explosions occurred seconds apart outside Ankara's main train station as hundreds were gathering for the rally, organized by Turkey's public sector workers' union and other civic society groups. The rally was to call for increased democracy and an end to the renewed violence between Kurdish rebels and Turkish security forces.
There was no immediate claim of responsibility for the deadliest attacks in Turkey in years.
The attacks came at a tense time for Turkey, a NATO member that borders war-torn Syria, hosts more refugees than any other nation in the world and is holding a general election on Nov. 1.
Authorities had been on alert after Turkey agreed to take a more active role in the U.S.-led battle against the Islamic State group. Turkey opened up its bases to U.S. aircraft to launch air raids on the extremist group in Syria and carried out a limited number of strikes on the group itself. Russia has also entered the fray on behalf of the Syrian government recently, bombing sites in Syria and reportedly violating Turkish airspace a few times in the past week.
Turkish jets have also carried out numerous deadly airstrikes on Kurdish rebel targets in northern Iraq. Some 150 police and soldiers and hundreds of rebels of the Kurdistan Workers' Party, or PKK, have been killed since July, when the conflict flared anew.
Busloads of activists had travelled to Ankara from other cities to attend Saturday's peace rally. Health Minister Mehmet Muezzinoglu said 62 of the bomb blast victims in Ankara died at the scene, while 24 others died after being taken to the hospital.
An Associated Press photographer saw several bodies covered with bloodied flags and banners that demonstrators had brought with them for the rally. Police later cordoned off the area.