Weekend suicide bombings that killed at least 97 people in the Turkish capital deepened turmoil and political polarization in a country that is central to both the battle against extremist group Islamic State and the migrant crisis in Europe.

On Sunday, protesters assembled a short distance from the site of the worst terror attack in Turkey’s modern history. They occasionally broke into antigovernment chants, calling President Recep Tayyip Erdogan a “murderer” as they accused the state of failing to prevent the assault.

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