At least 31 people have lost their lives in one day during the annual Hajjinfo-icon pilgrimage in Saudi Arabiainfo-icon.

The official Saudi Press Agency (SPA) reported on Monday that 31 pilgrims, all foreign nationals, had died on Sunday, without elaborating on the cause of their death

The report said more than 620,000 pilgrims had thus far traveled to Saudi Arabia to perform the Hajj rituals.

The kingdom organizes and administers the Hajj pilgrimage in the cities of Mecca and Medina.

Following two deadly incidents in September 2015, serious questions were raised about the competence of the Saudi authorities to manage the Hajj rituals.

Back then, over 100 pilgrims lost their lives when a massive construction crane collapsed into Mecca's Grand Mosque. Thousands of people also perished in a human crush that same month.