DIESEL OIL in a river was not the cause of a chemical incident in Colchester, according to the Environment Agency

A business park was evacuated and a dozen people were taken ill after a suspected chemical leak in Colchester.

Ten people received medical treatment from the ambulance service following a suspected chemical leak near Colchester's Royal Mail depot.

Two others managed to move away from the suspected leak and recover themselves.

Residents and workers by the Moorside Business Park, near East Street, began feeling unwell shortly after 3am yesterday.

Emergency services were called to the scene and ordered people into their homes and set up a quarter mile cordon around the Royal Mail.

It is not yet clear where the leak came from or what chemicals made people ill.

Royal Mail claim the leak was not from its premises.

Environment Agency specialists worked with fire crews to find out if the chemicals came from the River Colne, which is behind the depot. 

A spokesman said the investigation has been closed after experts ruled out a connection between the oil and the illnesses suffered.

Four fire crews and several specialist vehicles were sent at 3.44am.

On arrival they declared a "hazardous material event" and put into place several safety procedures.

Cordons were then set up by police and paramedics began treating the sick.

A spokesman for the East of England Ambulance Service said: "We were called to an incident at the Royal Mail depot in Moorside, Colchester at 3.41am.

"Two ambulances, four hazardous area response team vehicles, one rapid response vehicle and an ambulance officer attended the scene and treated ten people.

"Three were conveyed to Colchester General Hospital with ailments such as headaches and sore throats from inhaling chemical fumes.

"Seven other patients have been released as walking wounded."

Fire crews began trying to find the source and test the chemicals.

Divisional Officer Gary Jeffrey, speaking from the scene shortly after arriving, said: "We are treating this as a hazardous material event and are working to identify the chemical involved and find where it has come from.

Gazette:

"Some people have been affected but we have managed to get them indoors where the effects appear to be wearing off."

By 6.30am ten people have been removed from the area to get clean air and were being treated by the ambulance service.

Other workers, including those for Royal Mail, were evacuated outside of the cordon.

East Street was closed at the junction to Brook Street to the Greenstead Road junction.

By 7.30am two fire engines remained on scene with a detection, identification and monitoring vehicle to try and find out what hazardous material caused the illness.

Mr Jeffrey added: "Crews have carried out investigation work and no trace of any chemical has been detected.

"One possible cause could be diesel in the River Colne and the Environment Agency is currently establishing any link to the incident."

A spokesman for Royal Mail said: "We can confirm ten members of night-shift staff at Royal Mail’s Colchester delivery office were evacuated at 4am on the advice of the fire service, after smelling chemicals.

"Staff started returning on-site at around 9.15am after the fire service and Royal Mail’s internal safety team declared the office to be safe.

"The fire service put a quarter mile cordon around the office as a safety measure while they investigated.

"The cause is still not known but Royal Mail have been advised it did not originate from our site.

"Ten members of staff received medical attention to check they were ok and three members of staff were taken to hospital as a precaution and have now been released from hospital."

Tests carried out by the fire service also came back negative meaning the cause remains a mystery.