Please attribute to a South East Coast Ambulance Service
(SECAmb) spokesperson:

“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.”