A BOMB alert has been received by Madrid airport about a Saudi Airlines flight due to take off for the capital, Riyadh.
Airline governing body AENA says the plane had not taken off yet and had been moved to a secure area of the Adolfo Suárez-Barajas airport.
Flight SVA 226 was due to take off at 10.54hrs this morning (Thursday).
Some passengers had already boarded, but have been evacuated and moved to an airport lounge.
At first, the alert was said to be general, but it was later specified as affecting the Saudi Arabia flight.
The alarm was raised by the captain of the plane, but the exact reason for the alert is not known.
It could relate to anything from a bomb through to a breakdown in the landing system, but those close to the scene believe it to be the former.
But it is hoped to be just a hoax, since terrorist cells such as DAESH and Al-Qaeda do not normally give warnings.
Interior ministry sources say the TEDAX explosives deactivation squad has been drafted in.
The rest of Madrid airport is running normally.