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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There are now more than 25 million people on the NHS Organ Donor Register, representing 38% of the UK population.
Dry morning with plenty of sunshine. Cloud will gradually thicken into the evening but it will remain largely dry.
It will be a fine morning with sunshine but cloud will increase with patchy light rain reaching some areas throughout the day.