Police have been assisting ambulance crews at HMP Lewes after prisoners and staff became unwell due to suspected food poisoning.
Those affected are thought to have eaten the same meal and no one is considered to be in a life-threatening condition or seriously ill, according to officials.
Three inmates and three staff members at the category B prison have been taken to hospital. Nobody else is expected to require hospital treatment.
HMP Lewes has not been locked down and there is not thought to be any evidence that the incident is linked to drugs.
A Prison Service spokesperson said: “We are working with the emergency services to deal with a suspected food poisoning incident at HMP Lewes.”
An incident support van with the letters “CBRN” – which stands for chemical, biological, radiological and nuclear – has been seen outside the prison.
Meanwhile what appeared to be a decontamination tent was erected outside Eastbourne District General Hospital.
There was also a sign outside the hospital reading “major incident” and “site closed”.
The East Sussex Healthcare NHS Trust has said the Eastbourne District General Hospital was “stood up to potentially receive casualties following an incident at HMP Lewes”.
However, it said the hospital has been stood down and “care at the hospital has not been affected”.
Read more from Sky News
Disgraced ‘crypto king’ jailed for 25 years
Man arrested over Gogglebox star’s death
Signs that were put up outside the Eastbourne District General Hospital. Pic: Eddie Mitchell
Maria Caulfield, the Conservative MP for Lewes, has said in a statement on the X social media platform: “Concerned to hear about the incident at Lewes prison. Emergency services are on scene and it is important to let them deal with the situation in looking after those affected.”
A spokesperson for Sussex Police said: “Sussex Police are assisting the ambulance service following the report of a medical incident at HMP Lewes at around 12.30pm on Thursday [28 March].”
