Four people were taken to hospital last night after what police have described as an "incident" at a Royal Mail centre in Aberdeen.
The emergency services were called to the site at Wellington Circle in Altens on Thursday evening.
Police said the people who were unwell were later released from hospital.
A Royal Mail spokesperson said: "Emergency services assessed Aberdeen Mail Centre on Thursday evening and confirmed our staff could return."
The statement added: "The health and safety of our staff is our highest priority.
"We are following emergency services guidance and we will keep talking to and working with our employees.
"We can confirm that there was minimal disruption to our operation as a result of the incident."
A Scottish Ambulance Service spokesperson said: "We received a call to attend an incident at Wellington Circle in Altens.
"We dispatched two ambulances, our special operations team and a manager to the scene. We transported two male patients and two female patients to Aberdeen Royal Infirmary."