Mystery surrounds an incident at a Rotherham call centre after staff started feeling sick and suffering eye irritation.
Emergency services were called to the Capita call centre on the Manvers Industrial Estate, Wath-upon-Dearne, at around 7.50pm last night.
Crews from Dearne, Cudworth, Mansfield Road, Mosborough and Central stations arrived to find call centre workers being treated by paramedics.
They suspected a chemical had caused the sickness and eye problems but were unable to establish what had been responsible.
A South Yorkshire fire service spokesman said: “ Last night we attended a suspected chemical incident at Brookfield’s Park on Manvers Industrial Estate, Rotherham.
“Crews were called to offices at around 7.50pm to reports of people suffering the effects of nausea and eye irritation.
“Appliances attended from Dearne, Cudworth, Mansfield Road, Mosborough and Central stations.
“Fire and rescue officers entered the premises with equipment to monitor the air quality, after the building had been evacuated but found no materials that could have been the cause.
“We worked with our partners in the Yorkshire Ambulance Service, who are checked approximately 75 people over at the scene.
Fire crews left the scene around 10:30pm.”