THE county's postal service was getting back to normal after two Royal Mail sorting offices in the area received suspicous packages, feared to be anthrax.

Staff at the Preston delivery office, on Christian Road, went back to work at around 12.30pm, after a powder, suspected to be anthrax, was found to be a medicinal compound.

A spokesman for the Royal Mail said: "Things should be more or less back to normal tomorrow.

"The first delivery went out on time, and any mail that isn't delivered today should go out with the mail tomorrow.

"We are catching up."

Staff were locked inside the Christian Road office from 9.15am for around an hour while emergency fire crews from the major incident support unit rushed to the scene.

Four postal workers were thought to have come in contact with the package containing powder believed to be anthrax.

But after on-the-scene examination one senior fire officer confirmed it was unlikely to be the deadly spores as it was the wrong colour.

Postal workers were allowed to leave the sorting office, which uses a platform on Preston railway station, at around 10.15am.

And police slammed anthrax hoaxers after a suspect package containing the name of Osama Bin Laden was sent to the Post Office's Blackburn sorting office.

Officers were called in and 190 postal workers told to stay inside the Canterbury Street building when the package was found at around 8am.

Environmental health officials isolated the substance inside and took it away for analysis.

However, a police spokesman said it was believed to be sand. There was another false alarm yesterday over a letter delivered to the London Stock Exchange.

A Royal Mail spokesperson said the sorting office was operating asgain normally by mid morning.

"The all-clear was given after the substance had been taken away for analysis," she added.

Deliveries to postal districts BB1, BB2 and BB6 were seriously delayed by the scare.

The incident comes the day after 400 postal workers in Liverpool were evacuated when a suspect package was sent to its main office. That contained sand.

Fears about the disease being released by supporters of Bin Laden have grown in this country after one man died and 13 others cases were confirmed in America.

Detective Chief Inspector Steve Hartley said: "As a matter of precaution some workers were told not to leave the premises while environmental health were called but we are happy that it is a hoax.

"It is quite clear that there is a danger that if people do contribute to these sort of incidents it will place a strain on all our resources and possibly spread fear among the community.

"If we find anybody responsible for these acts they will be prosecuted."

Health chiefs have told doctors across East Lancashire to be on their guard for the symptoms of anthrax although Lancashire police today urged people not to panic.

East Lancashire Health Authority has issued guidelines for GPs across the area for the first symptoms of the deadly bug, which have been released by the Department of Health and the Public Health Laboratory Service.

Although health bosses stress the chances of anthrax being released in this area are extremely remote, doctors are still being asked to be vigilant in the wake of four cases of anthrax poisoning in America.

Dr Roberta Marshall, consultant in communicable disease control for the health authority, said: "Given what has happened in the past few weeks in America, I think nobody would want to rule anything out.

"We have to be realistic. We have been advised that there is no specific alert but at the moment we have got to be wise to any potential risk there might be."

A spokesman for Lancashire Police said: "There is no specific suggestion that Lancashire is in any way being targeted.

"But we are aware that the public would be concerned about the possible threat of bio-terrorism.

"This constabulary -- along with others -- is in close liaison with other emergency services."