article_snippet.sent: Volcano Calbuco, which has laid dormant for more than 40 years, suddenly erupted on Wednesday causing a thick plume of ash to cloud the sky while thousands of people living in the sky shadow were forced to flee the 'apocalypse-like' event.
article_snippet.sent: Volcano Calbuco, believed to be among the three most dangerous of Chile's 90 active volcanoes, had erupted for the first time at 6pm local time on Wednesday.
article_snippet.sent: Previous and equally violent eruptions at Calbuco have continued for up to a week, according to a volcanologist from Oxford University who told MailOnline it is impossible to predict what will happen next.
article_snippet.sent: Volcano Calbuco's last major eruption happened in 1961, with a weak eruption following in 1972.
article_snippet.sent: the massive eruption at Calbuco volcano was seen up to 100 miles away in neighbouring Argentina.
article_snippet.sent: Unexpected: The volcano last erupted in 1972, and while The volcano is widely believed to be among Chile's most dangerous, it was not under observation before it erupted today (the eruption pictured from Puerto Varas
highlights_snippet.sent: Calbuco volcano in southern Chile - which has been dormant for 40 years - erupted without warning on Wednesday .
  