Tellez said the findings reinforced the idea that the crash was an accident, although the investigation continues.

'Blow to president'

Agustin Basave, a political scientist at the capital's UNAM university, said the accident was "a strong blow" for Felipe Calderon, the president, in his battle against the drug cartels.

Juan Camilo Mourino, the interior minister and the number two figure in the cabinet of Calderon, died on Tuesday when the government Learjet crashed in Mexico City.

The US-trained economist and former legislator was named interior minister in January, taking charge of internal security a year into Calderon's bloody, army-led battle against powerful drug cartels.

The crash killed all nine people on board and another five on the ground [AFP]
Jose Luis Santiago Vasconcelos, a leading Calderon adviser in the drug war and former deputy attorney-general with years of cartel-fighting experience, also died when the aircraft smashed into evening rush-hour traffic, setting cars ablaze.

All nine people on board and five people on the ground were killed.

The jet narrowly missed high-rise office buildings full of workers in an upmarket business district.

Analysts say that even without evidence, many Mexicans will suspect foul play in a country where fear of being a drug-gang target hangs heavily over government officials.

More than 4,000 people have died in drug violence this year, mainly traffickers in turf wars, but hitmen have also murdered a string of police chiefs in recent months.