Riyadh, Sept. 16 -- The Saudi-led coalition on Wednesday warned that the security of Islam's two holiest sites is a "red line" after Saudi air defences intercepted and destroyed a drone launched by Yemen's Houthi in the south of the holy city of Makkah Al-Mukarramah, popularly known as Mecca.

According to a statement issued by the coalition on Wednesday, the Royal Saudi Air Defence Forces intercepted the drone in the evening on Tuesday, before it could enter the prohibited airspace around Mecca.

Coalition spokesman Major General Turki Al-Malki described the incident as a "hostile and terrorist act", saying the drone had been launched by what he called the "Terrorist Houthi Militia".

"The security of the Two Holy Mosques and the pilgrim...