Pope Francis has denounced how migrants, the poor and marginalised see their "human dignity crucified" every day through injustice and corruption, and urged the faithful in an Easter Vigil message to keep hope alive for a better future.

Francis presided over the solemn evening ceremony in St Peter's Basilica at a time of heightened security fears following a spate of Islamist attacks and tensions over Europe's migrant influx.

Security was particularly tight, part of the heavier than usual safety measures that have been deployed around the world for Holy Week activities, particularly following the twin Palm Sunday attacks on Coptic churches in Egypt that killed at least 45 people.