Emergency services were rushed to farm in Kent after more than 50 fruit pickers struggled to breathe following a suspected chemical leak.
A major incident was declared this afternoon after workers started experiencing breathing difficulties at the site in the village of Langley near Maidstone.
More than 40 firefighters were scrambled to the farm, while ambulance crews treated 57 people at the scene.
The workers are believed to be foreign nationals, mostly in their twenties and thirties.
Nearby hospitals have put up special hazardous materials tents outside their A&E departments in preparation to treat those affected.
Emergency services are dealing with a suspected chemical leak at a farm in Langley, Kent
Workers at Maidstone Hospital and the Tunbridge Wells Hospital in Kent say they have set the tents up for safety reasons.
People are being urged to only use the A&E departments for ’emergency and life-threatening situations’ ahead of treating the casualties.
A spokeswoman for Maidstone and Tunbridge Wells NHS Trust, which runs the hospitals, said: ‘Our hospital sites are currently preparing for the arrival of a number of patients who are experiencing breathing difficulties following a suspected chemical incident in Maidstone.
‘As a precautionary measure, a hazardous materials tent has been erected outside the emergency department to help us manage those patients.
‘While our emergency departments are open as normal, we would encourage people to only use our EDs for emergency and life-threatening situations during this period to help us focus our resources on those who need it most.’
A fire brigade spokesman said: ‘Crews wearing breathing apparatus together with hazardous material officers are working to establish what the chemical is. The incident is contained to the site.
This is the fruit packing farm where 57 people have been treated for carbon monoxide fumes
‘Five fire engines, hazardous material officers and a specialist chemical unit are in attendance.
‘South East Coast Ambulance paramedics are looking after 57 people experiencing breathing difficulties.’
A Kent Police spokesman said: ‘Kent Police were contacted by South East Coast Ambulance Service at 2.49pm regarding reports of a suspected chemical leak at a commercial site near Sutton Road, Langley, Maidstone.
‘Officers are at the scene along with the Kent Fire and Rescue Service and ambulance crews, and are offering assistance where needed.’
A South East Coast Ambulance spokesman added: ‘We are responding to an incident in Sutton Road, Langley near Maidstone, following a suspected chemical leak at a premises reported to us at approximately 2.20pm today.
‘Ambulance crews, including our Hazardous Area Response Team and the air ambulance service, are at the scene.
‘We have assessed and treated 57 people at the scene for breathing difficulties. A number have been discharged from our care. No patients are currently in a serious condition.’