Spanish air traffic authority said that it has closed four airports including Madrid due to a lack of air traffic controllers ahead of a holiday weekend. Aena said the reason for the closures is that many controllers have not turned up for work, claiming to be ill, in what appears to be a covert strike, according to AP. Spain's air traffic controllers have been involved in a long negotiation process with state-owned Aena over wages, working conditions and privileges. Other airports closed at some of the country's main tourist destinations are Ibiza, Palma de Mallorca and Menorca _ in the Balearic Islands.
