The collapse of a crane in the Grand Mosque in Mecca, Saudi Arabia, on Friday evening left dozens of people dead and hundreds injured, Reuters reports.
The Saudi Civil Defense Authority confirmed via Twitter that 107 people were killed and at least 238 injured.
Few details have emerged from the scene thus far, but the director general of civil defense, Suleiman bin Abdullah al Amr, and his team are on the scene.
According to Al Jazeera's Hasan Patel, the mosque was crowded in anticipation of the 6:30pm prayer.
Pictures and video circulating on social media showed bloodied bodies strewn across the part of the floor where the crane landed. The crane appears to have crashed through the mosque's roof, and photos show debris littering the floor.
Al Arabiya reports that high winds caused the collapse, and reports on Twitter claim that the collapse occurred during a sandstorm. Lighting may have struck as well, according to Al Jazeera. Videos show people running, attempting to avoid sand and wind.
Earlier Friday, the Saudi Civil Defense Authority had warned of inclement weather on Twitter: "According to reports by the Presidency of Meteorology: Mecca will be exposed, in the next few hours, to heavy rain, God willing."
The governor of the region, Prince Khalid al Faisal, has ordered an investigation into the cause of the accident, reports RT.
The mosque was in the middle of preparations for this month's Hajj pilgrimage when the crane collapsed. Hundreds of thousands of Muslims from all over the world flood Mecca, Islam's holiest city. They are expected to make the journey at least once in their lifetimes.
Last year, Saudi Arabia had to reduce the number of pilgrims permitted to make the trip for safety reasons -- construction work was underway to enlarge the Grand Mosque, reports The Guardian.
The Indian consulate in Jeddah announced via Twitter that nine Indian pilgrims are believed to be injured.
Other photos and video from the collapse can be seen below.
Warning: some of the content is graphic.