MECCA, Sept. 17 -- Saudi Arabia's holy city of Mecca was placed under an emergency alert for the first time, warning of a possible aerial attack as fighting between Saudi forces and Yemen's Houthi rebel group intensified.

The alert was lifted within minutes, but the incident has triggered concern and anger across parts of the Muslim world while highlighting the wider tensions surrounding the conflict in the region.

The development has also raised questions about the much-discussed security understanding involving Saudi Arabia, Pakistan and Turkey, particularly after Pakistan reportedly stepped back from direct involvement in the conflict.

Amid the escalating threat, Israeli media have reported that Saudi Arabia and Israel held discussi...