Spain ramps up Gibraltar border checks

(file) This picture taken from Linea de la Concepcion, near Cadiz, on May 25, 2012 shows the famous Rock of the British colony of Gibraltar.
(file) This picture taken from Linea de la Concepcion, near Cadiz, on May 25, 2012 shows the famous Rock of the British colony of Gibraltar.

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    Spain ramps up Gibraltar border checks

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Tensions are flaring once again between the UK and Spain over the sovereignty of Gibraltar. CNN's Jim Boulden reports.