A Yateley woman is a “driving force” behind an animal rights activism group which repeatedly threatened companies connected with an animal testing laboratory, a jury has been told.

Heather Nicholson, of Pond Croft, Yateley, was a founding member of Stop Huntingdon Animal Cruelty (SHAC), Winchester Crown Court heard on Monday.

Since the group started in 1999 those involved have targeted secondary and tertiary companies supplying Huntingdon Life Sciences (HLS), in a bid to get them to stop their business with the animal testing lab, the trial was told.

On Monday Winchester Crown Court was told how Nicholson held a “managerial role at the top of end of the hierarchy” within the group.

The role continued even when the 41-year-old was serving a prison sentence, prosecutor Michael Bowes QC said.

He added: “Even though the terms of an anti-social behaviour order prevented her from taking an active part in demonstrations she remained very involved in the organisation.”

Nicholson along with Gerrah Selby, formally of Aldershot Road, Church Crookham, Daniel Wadham, formally of Pond Croft, Yateley, Gavin Medd-Hall, from Croydon and Trevor Holmes, from Crawley, deny conspiring together between November 15 2001 and May 2, 2007, to blackmail those companies they believe to be associates of HLS.

All the defendants - for photos see the ' view gallery' section above right - deny the charges.

SHAC would try to stop those companies doing business with HLS by publishing their details – names, addresses and other contact information – on their website, the prosecution told the court.

As a result the company would become a target of activism such as demonstrations, sending hoax bomb threats, criminal damage and threatening emails, the jury heard today.

SHAC was also involved in threatening people with AIDS and accusing people of paedophilia, the court heard.

Once a company said it would cease all business with HLS, SHAC would publish the admission on their website.

The jury was shown examples of hate mail including a note saying “the animal rights militia does not tolerate filthy, sick, evil, perverted scum like you”. See our picture gallery (above right) for some of the evidence put before the court.

Pictures were also shown of a used sanitary towel sent to a victim who was threatened with AIDS.

The court was told that Selby, 20, joined SHAC in 2006 while living in Church Crookham.

She took part in demonstrations in both the UK and Europe as well as working in the SHAC’s headquarters in Lower Common, Eversley, Mr Bowes said.

Wadham, 21, became involved in 2005 when he was living with Nicholson in Yateley, the jury heard.

Mr Bowes said Wadham was a “regular” at demonstrations until he was sent to prison for affray in 2006.

Mr Bowes told the jury people were entitled to have strong views however he said the actions taken by SHAC had “nothing to do with lawful expressions or freedom of speech and everything to do with blackmail”.

“The methods I have described were undoubtedly menaces and I submit, clearly blackmail,” he added.

The trial continues.