Saudi Arabia on Monday warned of a temperature spike in Mecca as Muslim pilgrims wrapped up the hajj in searing conditions, with more than a dozen heat-related deaths confirmed.
One of the world's largest religious gatherings unfolded during the oven-like Saudi summer again this year, and authorities recorded more than 2,700 cases of "heat exhaustion" on Sunday alone, the health ministry said.
On Monday temperatures were forecast to go as high as 49 degrees Celsius (120 degrees Fahrenheit) in Mecca, Islam's holiest city where pilgrims were circling the Kaaba, and in nearby Mina, where others were throwing stones at three concrete walls -- a ritual known as "stoning the devil" that is the last major step of the hajj.
"The holy sites today record the highest temperatures since the beginning of hajj... with a degree that may reach 49 degrees Celsius, and we advise the guests of God not to be exposed to the sun," the health ministry said, according to the state-affiliated Al-Ekhbariya channel.
Jordan's foreign ministry said on Sunday that 14 Jordanian pilgrims had died "after suffering sun stroke due to the extreme heat wave", and that 17 others were "missing".
Iran reported the deaths of five pilgrims but did not specify the cause, while Senegal's foreign ministry said that three others had died.
The Saudi health ministry announced 2,764 cases of heat exhaustion on Sunday due to sun exposure and "non-compliance with guidelines", which include taking shelter from the sun during the hottest times of day in the afternoon.
"Prevention is the most important, and the commitment of pilgrims not to go out at peak times except when necessary, or to use an umbrella, would reduce the incidence of heat exhaustion," the statement said.
"Our health guidelines for the coming days are clear and easy: carry an umbrella, drink water regularly, and avoid exposure to the sun."
The hajj is one of the five pillars of Islam and all Muslims with the means must perform it at least once.
This year's hajj drew around 1.8 million pilgrims, 1.6 million of them from abroad, according to Saudi authorities.
Hosting the hajj is a source of prestige for the Saudi royal family, and King Salman's title includes "Custodian of the Two Holy Mosques" in Mecca and Medina.