A Prison Service source suggested the prison van ambush would probably involve one of the escapees having access to a smuggled mobile phone.
A phone call could then be made or a text sent to let the armed gang know which prison van they were in and so which vehicle to target, among the number of vans making their way from jail to Manchester Crown Court.
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The boy was found unconscious and in cardiac arrest and was rushed to hospital where he died.
The victim, who was wearing her uniform at the time, was found knocking on doors nearly four hours after she was abducted.
There will be gales across Scotland and northern England this morning, but these will gradually ease through the afternoon.