(CNN) Hundreds of Italian mayors and thousands of citizens took to Milan's streets on Tuesday in a show of solidarity for a Holocaust survivor who was put under police protection after receiving anti-Semitic threats.

Senator-for-life Liliana Segre, 89, was only 13 when she was deported to Auschwitz.

She later became a vocal campaigner against racism and hate, recently spearheading the creation of a parliamentary committee against hate, racism and anti-Semitism, also known locally as the Segre commission.

She became the target of hundreds of social media attacks each day, the Milan-based Foundation Jewish Contemporary Documentation Center told CNN.

Organized by the Italian mayor's association, the Milan demonstration escorted Segre through the shopping arcade Galleria Vittorio Emanuele II to the main square, Piazza Scala.

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