At least seven people were known to have survived, however. They included, according to a Red Cross official in Cali, a husband and wife identified as Gonzalo and Nancy Dussan Delgado, and their two young children, as well as two women and a man.
Another report, by Caracol radio, put the number of survivors as high as 17. A commentator, describing a "Christmas miracle'', said a 19-year- old student, Mauricio Reyes, had been rescued by his elder brother, Juan Carlos, who rushed to the crash site.
Caracol said the survivors also included a girl about seven years old who had been found trapped in the wreckage.
Colombian civil aviation officials said they could not rule out sabotage in the crash. The fact that it occurred on the seventh anniversary of the Lockerbie disaster according to British time - although it was 20 December, local time - appeared unlikely to be more than coincidence. But the plane's destination, Cali, is home to the world's biggest cocaine cartel, most of whose leaders are now in jail and have threatened both the Colombian and US governments with terrorist attacks if they are not granted leniency.
Colombian officials were trying to find out whether any known cartel figures had been on board the crashed plane, American Airlines Flight 965, which took off from Miami International Airport at 6.35pm.
An FBI spokesman in Miami said two US newspapers had received unsigned faxed letters on Monday warning of bomb attacks on flights from Venezuela or Colombia. But he noted that the letter said "from" not "to", and said it did not appear related to the crash.
The plane went down in what Colombian security forces regard as a "hot zone", an area largely controlled by Marxist guerrillas who in the past have destroyed the radio beacons which help pilots locate their position. Equally, the terrain in the area is known to be difficult.
Robin Rackham, a pilot who has flown extensively for Avianca in the region, said that like most Colombian airports, Cali's is in a valley and requires very careful flying. "There are mountain peaks reaching 16,000 or 17,000ft in the region and you are always worried about getting lost," he said. "At this time of the year there is the added hazard of frequent thunderstorms which you have to fly around." Mr Rackham said that while Cali has modern navigation equipment, the controllers' command of English, the international language of aviation, is limited. "It is a very hostile environment in which to fly," he added.
Mr Rackham said the location of the accident, 64 miles from the airport, indicated that the pilot had begun his descent from the cruising height of about 30,000ft. At the normal rate of descent, the plane should have been at an altitude of about 20,000ft at that distance from the airport.
The chairman of American Airlines, Robert Crandall, told his employees he was "horrified and mystified" by the crash. At a later news conference, he said visibility in the crash area was good; there was neither wind nor rain; the plane had been overhauled this year, and the experienced pilot knew the Cali area well.
Eyewitnesses described human limbs and clothes dangling from trees and scattered across the San Jose mountainside near Buga, 40 miles north of Cali, and the plane, which crashed in a "fireball", in small pieces.
That made all the more remarkable local radio reports of survivors. American Airlines, one of the biggest US carriers, said it believed all 156 passengers and eight crew members had died. Survivors would suggest that the plane did not break up in mid-air and the most likely cause was that a navigation error caused it to fly into a mountain, Mr Rackham said.
It was the first accident involving the Boeing 757, first flown in 1982 and used by 46 airlines in 20 countries. Last month, the Federal Aviation Administration in Washington downgraded its assessment of Colombia's civil air authority to a conditional safety rating after it found shortcomings in its international standards. Nearly 1,000 people have been killed in aviation accidents in the country in the past 10 years.
In 1993 the International Airlines Passenger Association recommended that its members avoid flying in and out of Colombia.
The country, it said, had a 1983-92 accident record that was 20 times higher than that of the United States.Reuse content