Investigators are trying to find out what caused a Spanish tourist jet to break up in flames as it took off from Madrid's airport, killing 153 people in the country's worst air disaster in decades.
One engine of the Spanair MD-82 caught fire during the attempted take-off from Madrid-Barajas airport on a flight to Las Palmas in the Canary Islands at 2.45pm (2245 AEST) on Wednesday, Spanish media said, quoting witnesses.
The unstable aircraft then veered off the right side of the runway, before breaking up, with fire spreading rapidly through the fuselage.
Spain's Transport Minister Magdalena Alvarez said 153 people were killed and 19 injured, two of whom remain unidentified.
There were 162 passengers on board along with 10 crew members, four of whom were travelling as passengers. Twenty two children were among the passengers, two of them infants.
Alvarez said the MD-82 had just taken off, but it was not clear if the back wheels had left the ground.
She said the plane had earlier begun taxiing to the runway, before turning back because of an undisclosed technical problem, which caused a one-hour delay in the take-off.
The two black boxes were found and were to be analysed.
Some experts said the fire in the engine was not enough to explain the accident, and other factors may be involved. The plane should have veered to the left if there was a loss of power in the left engine.
Spanish media said the pilot had earlier signalled a malfunction in an exterior temperature gauge, which was fixed before take-off.
The 15-year-old plane was bought from Korean Air nine years ago, and was overhauled early this year, Spanair said.
Secretary of State for Communication Nieves Goicoechea ruled out terrorism, saying there was "no doubt that it was an accident".
The head of the emergency and rescue services in Madrid, Ervigio Corral, earlier said the bodies were scattered over a wide area, and some of the survivors were able to "walk away" from the accident.
At the airport, distraught friends and family members of those on board were escorted into a special room, where priests and psychologists were there to counsel them. Dozens more waited at Las Palmas airport.
Spanair, Spain's second largest airline after Iberia, released the list of passengers late Wednesday, but not their nationalities. However, Spanish media said four Germans, two Swedes, a Chilean and a Colombian were among the survivors.
No Australians are thought to have been aboard the jet, authorities say.
The Department of Foreign Affairs and Trade said the Australian embassy in Madrid had been checking with local authorities.
"We are not aware of any Australians involved in the incident, however, our embassy in Madrid is in contact with local authorities, hospitals and the airline to ascertain if any Australians are affected," a DFAT spokeswoman said.
Australians concerned about family or friends travelling to the Canary Islands can contact DFAT's 24-hour consular emergency centre on 1300 555 135 in Australia or +61 2 6261 3305 for overseas callers.
The flight was a codeshare with Lufthansa and the German carrier said four passengers from a Lufthansa flight were registered on the ill-fated Spanair jet and had arrived in Madrid.
Spanair's managing director Marcus Hedblom described it as "the worst thing that could happen" and expressed his condolences to the families of those killed.
SAS, the Scandinavian airline which owns Spanair, said a special team had been set up in Madrid.
Spanish Prime Minister Jose Luis Rodriguez Zapatero, who interrupted his holiday to go to the scene, said "the government is overwhelmed, very affected, as are all Spanish citizens, by this tragedy".
Italian President Giorgio Napolitano expressed his condolences in a message to Spanish King Juan Carlos.
"At this sad moment, Italy, united with your country by traditional bonds of friendship, feels particularly close to the Spanish people," he said.
German Chancellor Angela Merkel was said to be shocked by the number of dead and injured, according to spokesman Thomas Steg.
The chancellor shares the pain of the families who have lost loved ones, he said, adding that she too had sent a message of sympathy to Zapatero.
French President Nicolas Sarkozy said he had learned of the "terrible" accident "with great sadness" adding that his thoughts were with the injured and victims' families.
A spokesman for British Prime Minister Gordon Brown said the prime minister was "deeply sorry to hear about today's tragedy in Spain".
"His thoughts are with the Spanish people and all those affected by the tragedy."
Queen Elizabeth II said she was "shocked" and "saddened" in a message to King Juan Carlos.
"Philip joins me in sending our warm and heartfelt sympathies to the families and friends of those who have died and our best wishes for a speedy recovery to those who have been injured," the British monarch added, referring to her husband Prince Philip, the Duke of Edinburgh.
"At this difficult time all those affected by this tragedy are in our thoughts and prayers."
Spanair was founded in 1986 and says it has carried more than 104 million passengers from about 100 European destinations since then. It has a fleet of 65 jets.