At least 87 people were killed when a crane crashed in Mecca’s Grand Mosque on Friday, Saudi Arabia’s civil defence authority said on its Twitter account. Over 180 people were wounded, the civil defence authority tweeted.
It is not clear what happened, but images on social media appeared to show part of a huge crane had crashed through the mosque roof.
Hundreds of thousands of people are expected to arrive in the Saudi city from all over the world later this month.
The Muslim annual Haj pilgrimage is due later this month and Saudi authorities go to great lengths to be prepared for the millions of Muslims who converge on Mecca.
Last year, the kingdom reduced the numbers permitted to perform haj for safety reasons because of construction work to enlarge the Grand Mosque.