Starting his first full day in the Kenyan capital, Francis met Muslim and other religious leaders before saying an open-air Mass for tens of thousands of rain-drenched people who sang, danced and ululated as he arrived in an open pope mobile.

"All too often, young people are being radicalised in the name of religion to sow discord and fear, and to tear at the very fabric of our societies," he told about 25 religious leaders.

Inter-religious dialogue "is not a luxury. It is not something extra or optional, but essential," he told them, stressing that God's name "must never be used to justify hatred and violence."

In his homily at the Mass, Francis urged the faithful "to resist practices which foster arrogance in men," speaking in a nation rattled by a series of corruption scandals.

Thousands of police officers, some mounted on horses, were deployed in Nairobi to protect the pope and control the crowds.

Read more: Pope Francis heads to Africa hoping to bridge Christian-Muslim fault lines

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