Jerry Petherick, managing director for G4S Custodial and Detention Services, said: "The mobilisation of any prison is a complex and challenging operation but the size and scale of Oakwood - the largest prison in the country - made this even more acute.
"As well as the logistical hurdles in new establishments, prisoners test the regime as well as the members of staff, who may be new to prison life.
"We have already taken steps to make improvements, appointing a dedicated task-force to address problem areas, such as the prevalence of drugs, while providing additional funding where necessary. This is starting to yield results."
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Feeling less cold than recent days with winds easing and some long sunny periods. Most areas will be dry throughout.
A cold start with some icy patches. Largely dry and sunny through the day, with any showers soon dying out and winds easing too.
Scattered wintry showers during the evening will become fewer and further between overnight, with westerly winds tending to ease.