The death toll from this year’s hajj has exceeded 1,000, an AFP tally said, more than half of them unregistered worshippers who performed the pilgrimage in extreme heat in Saudi Arabia.

The new deaths reported Thursday included 58 from Egypt, according to an Arab diplomat who provided a breakdown showing that of 658 Egyptians who passed away, 630 were unregistered pilgrims.

All told, around 10 countries have reported 1,081 deaths during the annual pilgrimage, one of the 5 pillars of Islam which all Muslims with the means must complete at least once. The figures have come via official statements or from diplomats working on their countries’ responses.

The hajj, whose timing is determined by the lunar Islamic calendar, fell again this year during the oven-like Saudi summer.

The national meteorological centre reported a high of 51.8 degrees Celsius this week at the Grand Mosque in Mecca. According to a Saudi study published last month, temperatures in the area are rising 0.4 degrees Celsius each decade.