Maryland state governor Wes Moore has said that a cargo ship lost power before smashing into one of the columns supporting the landmark Francis Scott Key Bridge in the city of Baltimore, causing its collapse. Several vehicles were crossing the bridge when the container ship collided with one of its supports. Six people are unaccounted for and a number of vehicles fell into the water. Officials said the ship suffered a "power issue" and issued a Mayday distress call moments before the crash. Boats and helicopters are part of a huge search and rescue effort searching for the missing people. The authorities said they were part of a construction crew repairing potholes at the time the bridge collapsed. . Two people were pulled from the water, with one in a serious condition. The Singapore-flagged container ship, Dali, struck a support column on the bridge after departing from the terminal at Port Breeze, bound for Sri Lanka. A US federal government agency said the vessel "lost propulsion" as it was leaving the port. The crew then warned Maryland transport officials of a possible collision, according to an unclassified Cybersecurity and Infrastructure Security Agency report on the incident. Sophie Raworth presents BBC News at Ten reporting by Sumi Somaskanda, Gary O’Donaghue and Rebecca Morelle. Subscribe here: http://bit.ly/1rbfUog For more news, analysis and features visit: www.bbc.com/news #BBCNews