Two men have been arrested and two parcels seized police believe were due to be thrown over the perimeter fences of a prison for inmates inside.
Detectives said they contained 'contraband' and didn't elaborate further.
Dawn raids were carried out on two addresses in Salford on Friday - with specialist sniffer dogs deployed in subsequent searches.
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GMP said the warrants executed came as part of an operation carried out by the force's new 'Challenger Prison Team'.
Set up this month, the unit is targeting organised crime linked to the four prisons in Greater Manchester and includes the investigation of so-called 'prison throw
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