But that will depend on persuading all EU countries to share passenger and crew list information - quite a number of them regard this as illegal under European free movement laws.

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With Circles, users can more quickly send certain messages to a particular crew, such as siblings or frat buddies, that they wouldn't want to share with their entire list of contacts.

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Add environmentalists and hunters, as well as the crew of a helicopter called in to rescue one poorly Lopez-fan from the vertiginous amphitheatre, to the long list of locals who bristle at the name of Mortier.

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