More than 107 people were killed and 238 injured Friday after a thunderstorm toppled a heavy construction crane at the Grand Mosque -- Masjid al-Haram -- in Mecca. The crane fell, crashing through the ceiling of the mosque, the largest in the world surrounding the site of the Kaaba, considered Islam's holiest spot.
The thunderstorm began over Mecca at about 4 p.m. local time (9 a.m. ET) on Friday. The crane crashed into the ceiling of mosque just before 6:30 p.m. during prayers, a busy period at the mosque, according to the Saudi Interior Ministry.
The Saudi civil defense agency had reportedly issued extreme weather warning before the fatal incident, which comes about 10 days ahead of the start -- September 21-26 -- of the annual Hajj pilgrimage, a time that hundreds of thousands of Muslims from around the world converge on the city of Mecca in preparation for the Hajj.
Photos uploaded to social media show the huge red crane being struck by lightning before it collapsed into the ceiling of the mosque, over the east side of the complex filled with worshippers, causing death and destruction.
The crane crashed through the ceiling, sending heavy chunks of concrete debris falling down on people below.
Among the 107 dead were nine Indians, 16 Pakistanis, and 15 Iranians.
Photos that emerged on social media after the accident show the chaos inside the mosque. The floor of the mosque was smeared with blood and littered with human bodies as people fled in panic over rubble-strewn floor.
There was a large crater on the floor where the crane collapsed.
Rescue and medical workers, including workers from the Saudi Red Crescent, rushed to the site immediately after the accident. Images uploaded to social media show the emergency workers carrying bodies out of the mosque.
The head of the Saudi civil defense agency confirmed later that all the dead and wounded had been taken to the hospital.
Meanwhile, the governor of Mecca, Prince Khaled al-Faisal, has ordered investigations into the cause of the accident. But the authorities have acknowledged it was caused by strong winds amid heavy thunderstorm.
Local media reports indicated that concerns had been raised previously about safety at the site surrounded by multiple heavy construction cranes.
The crane involved in the accident reportedly belongs to a construction company owned by the influential Bin Laden family. The company was involved in a project launched in 2011 by late King Abdullah bin Abdul-Aziz to expand the capacity of the mosque so that it can accommodate up to 2.2 million people.
The Bin Laden Group, founded by Mohammed, the father of Osama Bin Laden, regularly secures contracts for major civil engineering projects in the Saudi Kingdom.
The latest tragedy is yet another in a long history of similar tragedies during the Hajj season in Mecca. The pilgrimage to Mecca -- one of the five pillars of the Islamic faith -- involves one of the largest gatherings of people in the world, thus creating conditions that lead easily to fatal incidents, such as stampedes during popular Hajj rituals.
Other fatal incidents in the past were caused by protests, fires and bomb explosions.
More than 2 million pilgrims are expected to participate in this year's Hajj.
[Images: Getty; Twitter]