“Fourteen Jordanian pilgrims died and 17 others went missing” during the performance of haj rituals, Jordan’s foreign ministry said in a statement.

The ministry later confirmed the 14 had died “after suffering sunstroke due to the extreme heatwave”.

Iranian Red Crescent chief Pirhossein Koolivand separately said “five Iranian pilgrims have lost their lives so far in Mecca and Medina during the haj this year”, without saying how they died.

The haj, one of the world’s biggest religious gatherings, is one of the five pillars of Islam which all Muslims with the means must perform it at least once.

Temperatures have pushed well past 40°C during the annual pilgrimage that around 1.8 million Muslims are taking part in this year.

Many of the rituals are performed outdoors and on foot, creating challenges especially among the elderly.

Saudi Arabia has not provided any information on fatalities.

But the kingdom has implemented heat mitigation measures, including climate-controlled areas. It distributes water, and offers advice to pilgrims on protecting themselves from the sun.

During last year’s haj at least 240 people — many from Indonesia — died, according to figures announced by various countries which also did not specify causes of death.

More than 10,000 heat-related illnesses were recorded last year, 10% of them heatstroke, a Saudi official told AFP this week.

A Saudi study said regional temperatures were rising 0.4°C each decade, and worsening heat may be outpacing mitigation measures.