Examination of the wreckage began the morning after the crash
Accident investigators have begun examining the wreckage of a plane that crashed at Madrid's Barajas airport, leaving 153 passengers dead.
They will also start to analyse the flight data and voice recorders, which have both been recovered.
Three days of official mourning have been declared in Madrid, as relatives arrive at a makeshift mortuary in the capital to identify bodies.
Nineteen people survived the crash and several are critically hurt.
Of the 19 survivors of Spanair flight JK 5022, four are listed as being in a "very serious" condition, with another six only slightly better, Spain's El Pais newspaper reported on Thursday. Eight remain under observation with one only slightly injured, the newspaper said.
The worst is the identification of the bodies. It is the end of all hope
The Spanair flight, bound for Las Palmas in the Canary Islands, took off on Wednesday lunchtime with 172 people on board, among them 10 crew.
Initial reports suggested that a fire had broken out in one of the MD82 plane's engines during or shortly after take-off, and the plane ended up in a field.
Spanish Transport Minister Magdalena Alvarez said the plane had earlier begun taxiing to the runway, before turning back because of a technical problem, which had caused an hour's delay in the take-off.
Witness: Pilot had 'no going back'
Spanish media said the pilot had reported a fault with a temperature gauge, but it was thought to have been fixed.
Speaking on Thursday, Ms Alvarez said a thorough investigation would be carried out, with a full examination of the flight recorders and available pictures, but that it was very early to draw conclusions about the crash.
A special independent commission has been established to probe the cause of the crash, Spanish media reported.
Spanair has released the official passenger manifest, confirming reports that 20 children and two babies were on board the plane.
Among those who survived were three children, aged six, eight and 11, reports said. At least one of the 19 survivors has yet to be identified.
Overnight a long convoy of black hearses rolled out of the airport grounds to carry bodies to the makeshift mortuary, where the victims' relatives had gathered, some of whom had travelled from the Canary Islands.
The convention centre on the outskirts of the capital was also used as a mortuary after the Madrid train bombings four years ago.
The BBC's Steve Kingstone in Madrid says many of the relatives have expressed anger and disgust at Spanair, blaming it for the accident.
He says the injured include a young brother and sister, who immediately asked rescue workers about their parents.
Spanish ministers said foul play had been ruled out and the crash was considered to be an accident.
The 15-year-old plane had passed a safety inspection in January, said Sergio Allard, a spokesman for Spanair, which is owned by Scandinavian firm SAS.
Spanish media said some German, Swedish, Chilean and Colombian nationals had been among the passengers.
Spanish Prime Minister Jose Luis Zapatero cut short his holiday in the south of the country to visit the scene of the crash.
A convoy of hearses removed bodies from the scene of the crash
Speaking at the airport, he said that "the government is overwhelmed, very affected, as are all Spanish citizens, by this tragedy".
Television images on Wednesday showed plumes of smoke rising over the field in which the remains of the plane were resting.
Emergency services chief Ervigio Corral said that rescue workers had been faced with "a desolate scene".
"You couldn't distinguish that there was an aircraft there apart from the remains of the tail," he said. "There was nothing of fuselage."
Another rescue worker, Pablo Albella, told AP news agency: "The fuselage is destroyed. The plane burned. I have seen a kilometre of charred land and few whole pieces of the fuselage. It is all destruction."
Messages of sympathy have been sent to Spain by leaders around the world.
The presidents of Russia, France and Italy, Germany's chancellor and Britain's queen joined with Latin American leaders in sending their condolences.
It was the deadliest air accident in Spain since a Colombian airline's Boeing 747 crashed in Madrid in 1983 killing 181 people.
People concerned for relatives or friends who might have been on board the plane can call Spanair's helpline on +34 800 400 200 (calls possible from inside Spain only).
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