The Dutch populist daily De Telegraaf, quoting colleagues of the arrested Transavia pilot Julio Poch, says the pilot had never made a secret of the fact that he flew death flights for the Argentinean military junta. The paper also says that Transavia bosses knew about Mr Poch’s activities during the 1976 to 1983 military dictatorship.

Listen to a Newsline interview with human rights researcher Vidal Martin of Spanish think tank FRIDE:

The Argentine pilot, who also holds Dutch nationality, was arrested on Tuesday evening at Valencia airport in Spain at the request of the Argentinean justice ministry. Mr Poch is alleged to have carried out death flights; opponents of the military regime were thrown out of planes flying high above the sea. According to the Argentinean authorities, around 11,000 political opponents of dictator Jorge Videla disappeared during the Dirty War. Human rights groups say at least 30,000 people were murdered by the regime.

Julio Poch was arrested at Valencia airport just before takeoff on what was supposed to be his last flight before retirement. His son, who is also a pilot with Transavia, flew to Valencia with his wife to mark the occasion. The authorities must have made meticulous preparations for the arrest as Mr Poch's plane was only in Spain for 40 minutes. It appears that the Argentinean justice ministry was aware that Mr Poch was due to retire. His colleagues are mystified; why did Buenos Aires wait until now to make the arrest?

In 2005, Argentina's Supreme Court, at the behest of then-President Nestor Kirchner, struck down two amnesty laws that protected hundreds of people involved in human rights violations and war crimes during the dictatorship. Since then, a number of former security service personnel have been tried and jailed.

Transavia refused to comment on Mr Poch, apart from saying that he worked at the airline for a long time. The airline, a subsidiary of Air France-KLM, says it is investigating the way in which the pilot was hired. A spokesperson said they saw "no need to question Mr Poch's integrity as he had a Dutch passport".

It is not yet clear whether Mr Poch will face trial in Spain or whether he will be extradited to Argentina.