At least three men wearing dark clothes and balaclavas attacked a prison van in Manchester and threatened staff transporting the prisoners with a shotgun, police said.
The men arrived at the scene in a dark coloured Saab and freed prisoners Ryan MacDonald, 20, and Stevie McMullen, 31, Greater Manchester Police said.
The five men then got back into the car and drove a short distance before abandoning it.
Police believe they ran towards Phoebe Street in the Ordsall estate and that two possibly then rode a motorbike found abandoned on Thurlow Street.
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