A worker had to stay in hospital overnight after breathing in toxic vapours following a chemical leak at a food factory .

The employee was kept in as a “precautionary measure” due to the incident at English Provender Company plant in Saltney yesterday (April 9).

In total, 10 people were taken to the Countess of Chester Hospital with all but one being released later in the day.

The company, which manufactures hundreds of chilled products including mayonnaise, condiments and cooking aids, says the outcome of its internal investigation may not be known “for a number of days”.

Staff had to be evacuated following the incident – understood to have happened after two cleaning agents were mixed causing a release of toxic vapour – but were able to return to work by 4pm.