A senior police officer has issued a "don't panic" plea following anthrax scares in Essex, which have all turned out to be unfounded.

The sorting office in Chelmsford where mail for most of the county is handled was evacuated last Tuesday evening.

Assistant Chief Constable Joe Edwards said: "There's no evidence or intelligence to suggest that the UK has become a target for biological terrorism."

He added that anyone concerned about any package or letter they receive should ask themselves 'why should I be a target?'

Anyone who believes there is a genuine risk should contact the police immediately.

Mr Edwards said: "The emergency services and local authorities have well-rehearsed plans for dealing with incidents of all sorts, including chemical releases."

"If we have evidence that a letter or package has been sent as a deliberate hoax we will make every effort to identify and prosecute the person responsible."