At no time did the individual enter the cockpit

Interior Ministry spokesman

The man, identified as Perfecto Manuel Vazquez Exposito, allegedly became aggressive and drew a knife.

Earlier it was reported that the man had tried to hijack the plane, but officials say that this was not the case and that the man made no attempt to approach the cockpit.

"We are not talking about a hijack, but a disruption of public order by a Spanish citizen born in Cuba," said an interior ministry spokesman.

"When the plane was flying over Spain, an extremely drunk individual started threatening an air hostess and several passengers with a plastic cutter-type knife," the spokesman said, referring to the type of knife sold in hardware stores.

Distress signal

The incident forced the pilot to send an emergency distress signal and the plane was diverted to Torrejon air base near Madrid, escorted by two military jets.

Once safely on the ground it was stormed by special forces police, who took Mr Vazquez into custody.

The plane, operated by Avianca, was travelling from Bogota to Madrid's Barajas airport and had 148 passengers on board.

The flight had started in Mexico and had then picked up passengers in Bogota before heading for Madrid, the interior ministry spokesman said.

Security gap?

All of the passengers left the plane unharmed and were transferred by bus to Madrid's civilian airport.

Bogota airport security

Before check-in: 1. Police with dogs conduct random spot searches 2. Security specialists question passengers 3. All luggage is X-rayed and hand searched After check-in: 1. Luggage X-rayed 2. After passport control passengers pass metal detector 3. Police hand search bags 4. Passengers are submitted to pat-down search At gate: 1. Hand luggage X-rayed 2. Passports checked again 3. Police with dogs make visual checks

Spanish officials have been keen to stress that Mr Vazquez made no attempt to seize control of the plane.

"At no time did the individual enter the cockpit," the spokesman said.

The BBC's correspondent in Madrid, Mike Wooldridge, says it is not yet known how Mr Vazquez could have got a knife on board.

Airline security has been beefed up worldwide, since 11 September when hijackers armed with knives crashed passenger planes into New York's World Trade Center and the Pentagon in Washington, killing around 3,000 people.

Strict rules have since been imposed on the carrying of any type of sharp object in passengers' hand luggage.