At least 107 people were killed and more than 150 injured when a crane crashed through the ceiling of the Grand Mosque of Mecca amid high winds and thunderstorms today.
107 people dead and more than 150 injured at Mecca's Grand Mosque
The pilgrimage, one of the largest religious gatherings in the world, has been prone to disasters in the past, mainly from stampedes as pilgrims rushed to complete rituals and return home. Hundreds of pilgrims died in such a stampede in 2006.
Upsetting pictures circulating on social media showed bloodied bodies strewn across the floor where the crane came burst through the building.
The tragic incident in Saudi Arabia occurred shortly before the 6:30pm Friday evening prayer session - one of the busiest times of the week - causing devastation to what is the largest mosque in the world.
Hundreds of thousands of Muslims are gathering at the holy site from all over the world for the annual hajj pilgrimage set to begin later this month.
Saudi authorities have since lavished vast sums to expand the main haj sites and improve Mecca's transportation system, in an effort to prevent more disasters.
Security services often ring Islam's sacred city with checkpoints and other measures to prevent people arriving for the pilgrimage without authorization.
Those procedures, aimed at reducing crowd pressure which can lead to stampedes, fires and other hazards, have been intensified in recent years as security threats grow throughout the Middle East.
Last year, the kingdom reduced the numbers permitted to perform haj for safety reasons because of construction work to enlarge the Grand Mosque.
Al Jazeera's Hasan Patel, reporting from Mecca, said witnesses told him that a crane fell on the third floor of the Grand Mosque around 5.45pm.
Our correspondent said the mosque was packed, even though the incident happened shortly before the 6.30pm prayer.
'Dozens of ambulances are heading to the site. The authorities closed off the area shortly afterwards,' he said.
'This whole place is already a construction site. What made it worse is that around 5.30pm there was severe rain and it's just gushing down the road,' he said.
'I am surrounded by people who are grieving. The mood here is of sadness.'
Al Jazeera's Omar Al Saleh said bad weather was thought to be the cause of the accident - western Saudi Arabia has been hit by strong sand storms in the last few days.
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