Mexican President Andres Manuel Lopez Obrador has promised that his government will hide "absolutely nothing" concerning the helicopter crash in which opposition politicians Martha Erika Alonso and Rafael Moreno Valle died.
"In this government, there is a commitment and willingness to know the whole truth. We are not going to hide anything, we have to know what caused this accident and this tragedy," the leftist leader said at a press conference on Wednesday.
Lopez Obrador said that a transparent investigation would be carried out after some opposition leaders hinted at the possible participation of the president's Morena party or the current administration in the event.

Martha Erika Alonso and Rafael Moreno Valle have been killed in a helicopter crash. Source: Reuters
"So that there is no suspicion, the government of the republic will appeal to an independent body from abroad, recognised and prestigious, to present a conclusion that we are going to make public to the people of Mexico," he said.
Questioned about a possible conspiracy theory in the crash involving Morena, the president said that he is advocating for change in the country's politics via a "peaceful path".
"We are going to achieve this change along the path of harmony. We would never act against anyone," said Lopez Obrador, who criticised certain right-wing politicians and "neo-fascist groups" for acting in such a "petty way".

Relatives and friends touch the urn with the ashes of opposition leader Martha Erika Alonso. Source: AAP
Killed in the Christmas Eve crash were Puebla Governor Alonso and her husband and gubernatorial predecessor, Senator Moreno Valle.
An assistant from Moreno Valle named Hector Baltazar and the aircraft's pilot and co-pilot also died.

In a 2010 photo Rafael Moreno Valle, then-candidate of the "Compromiso por Puebla" party coalition, flashes two thumbs up after casting his vote. Source: AP
Lopez Obrador reported on Wednesday that the ongoing partial shutdown of the government in Washington is delaying a response to Mexico's request for assistance from the US National Transportation Safety Board.
Mexico's deputy transportation secretary, Carlos Alfonso Moran, said Tuesday that representatives of the Italian company that manufactured the Agusta A109 aircraft and of engine-makers Pratt & Whitney were already at the crash site in Puebla.
Alonso, of the right-wing National Action Party, took office December 14 after the federal electoral tribunal ratified her contested victory in the July 1 election over Morena candidate Miguel Barbosa.
The president called the electoral court's decision wrong and "anti-democratic".