"It is a gesture that provides a message of unity and repulsion, " Francisco Javier Ansuategui, the central government's Madrid representative, told Spanish news agency Europa Press at one gathering in the capital.

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The Moroccan ambassador to Madrid, Yamal Eddin Mechbal, called on his countrymen "to behave like civilised people, containing your rage and ire" in response to the attacks, the Spanish news agency Europa Press reported.

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