East Sussex Fire and Rescue Service has been called to Euro Business Park in Newhaven.
Crews are on the scene assisting Southern Gas Networks after a business had to be evacuated after a carbon monoxide alarm was triggered. They were called to the incident at 9.59 this morning (30 January).
Firefighters wearing breathing apparatus are currently carrying out a search of the building to identify the source.
Paramedics are at the scene looking after anyone affected.
Not been declared as a major incident and Sussex Police have a diversion for traffic in place.