The Bedfordshire, Cambridgeshire and Hertfordshire Major Crime Unit wants to trace anyone who saw a white Ford Transit-style van seen speeding from the Brunel Road area.

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The Italian foreign ministry has activated its crisis unit to try to trace Mr Quirico.

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But Mr Vine's report said the unit quickly became overwhelmed and failed to routinely or consistently make security checks to try to trace some of the unresolved cases subsequently archived.

BBC: The UK Border at Heathrow