Concerns over staffing pressures at Kent and Sussex prisons
Some prisons in south-east England are finding it a "real challenge" to recruit enough staff, according to the Chief Inspector of Prisons.
Charlie Taylor said competition from Border Force was adding to the recruitment pressures.
He said it was "particularly affecting" the three jails on the Isle of Sheppey in Kent.
The government says it is doing more than ever to attract and retain the best staff.
Mr Taylor, HM Chief Inspector of Prisons, told BBC South East staffing pressures were affecting Kent, Surrey and Sussex, including Rochester, Maidstone and Lewes prisons, along with Cookham Wood Young Offenders Institution in Rochester.
Steve Gillan, general secretary of the Prison Officers' Association said: "For example [HMP] Swaleside [on the Isle of Sheppey, Kent] is so short of staff they rely on 54 officers each day on detached duty to compliment their shortfalls in staffing levels.
"This means those prison officers are traveling from other establishments predominantly from the north of England to plug gaps."
Mr Taylor said the staffing pressures coincided with the rise in the prison population.
"We are seeing already prisons like Lewes [in East Sussex] and Elmley [in Sheerness, Kent] where there are many cells originally designed for one person being shared by two prisoners," he said.
"There's a lack of opportunities for prisoners to be able to progress, to be able to get to education and training and with the worry that the revolving door of crime, offending and prison just continues."
Prisons will be allowed to release some "less serious offenders" on probation early to relieve overcrowding in jails in England and Wales, the justice secretary has said.
The government has launched its first ever national TV and radio campaign to boost staffing levels.
The Ministry of Justice says it is aiming to hire 5,000 prison officers across public and private prisons by the mid 2020s.
Alex South, from Greenhithe, Kent, who was a prison officer for 10 years, said the service had lost many experienced staff over the last decade.
She said she had experienced very challenging working conditions.
"I have been present for incidents when officers have been assaulted with fists and weapons.
"The weapons were real knives that were being dropped off outside cell windows by drones."
She added: "It is understandable for people to decide that maybe, for their own health, the safest thing to do is to remove themselves from that environment."
A Prison Service spokesman said there had been an increase of over 700 prison officers in the 12 months ending 30 June 2023.
He said: "These efforts are working. We have hired over 4,000 additional officers since March 2017 and retention rates for prison staff are improving."
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