Alerted by the disruption caused to all air traffic by the Iceland volcano dust explosion in April 2010 to the power of using social media to communicate with frustrated passengers, KLM started intercepting their customers' Tweets and Facebook remarks and dreaming up little surprise, individualised gifts or events - when, at least, some of them travel.

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Institute Director Renato Solidum said the explosion early Tuesday was "steam-driven" and is considered "normal" activity for a volatile volcano like Mount Mayon.

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