The hold-up was so quickly and sharply executed that police are uncertain about how many people they are looking for. They say it is between four and six.
In radio interviews yesterday, the captain of the plane, Vincent Roy, who had flown the Airbus 320 on its hour-long flight from Paris, described what happened. "Just as we were about to leave the runway, two vehicles blocked our way," he said. "I called the control tower to ask what was going on, but then these armed and masked men came out, and I knew we were being held up."
According to Capt Roy, the gang raised a banner saying "turn off the engines and open up the hold" - an instruction which shocked him as much by its use of the familiar tu form of the verb (pilots are used to being treated with exceptional deference) as by its content. Hearing shots fired, he switched off the engine, but was cool enough to say that he had no way of opening the hold from the cockpit and told them to do it themselves - which they did.
Then, Capt Roy said, they went to the hatch closest to where the cargo from Brinks - the international transporter of valuables - was, removed two mailbags and drove out of the airport. No one was hurt.
The 173 passengers and crew were allowed to leave the plane 45 minutes later. Perpignan is the airport closest to south-western French Mediterranean resorts, and this is one of the busiest holiday weeks of the summer in France.
Whether through embarrassment or confusion, no definitive value has yet been placed on the loss. Until yesterday afternoon, the only information was that the two bags weighed 28kg. The value of the contents was first estimated at 4 million French francs (pounds 509,600), but it was later disclosed that the bags contained only Spanish pesetas, and that the value could be considerably less than first thought.
That such a hold-up could take place on the mainland raises serious questions about security, not just at Perpignan, but at other provincial airports. The gang was reportedly able to penetrate the runway area through a little-used back entrance that was concealed from the control tower by a mound. Local people use the mound as a vantage-point for watching the planes take off and it is also used by people coming to meet passengers. The robbers were able to wait there unsuspected.
Moreover, although the captain raised the alarm, the gang had fled the airport before anyone reached the scene. An official inquiry into the robbery was opened yesterday.
There is also a question about the transport of cash by air. Current French regulations require sums larger than 200,000 francs to be escorted by at least three guards when taken by road, but there are no similar regulations for the protection of air freight.