What's behind deaths at this year's Hajj pilgrimage in Saudi Arabia?

Hundreds of people are thought to have died during the Hajj pilgrimage in Saudi Arabia - most of them due to extreme heat as temperatures soared past 51 degrees Celsius.

AFP news agency quoted an Arab diplomat as saying 658 Egyptians had died. Indonesia said that more than 200 of its nationals had died. India said 98 people were known to have died.

Pakistan, Malaysia, Jordan, Iran, Senegal, Tunisia, Sudan and Iraq's autonomous Kurdistan region have also confirmed deaths. The US believes a number of Americans died, the Wall Street Journal reported. Friends and relatives have been searching for those missing in hospitals and posting messages online.