Seven animal rights activists - including one from Croydon and another from Chiswick - have been jailed for between four and 11 years for blackmailing companies who supplied Huntingdon Life Sciences.

Gerrah Selby, 20, from Chiswick and Gavin Medd-Hall, 45, from Croydon along with Heather Nicholson, 41, from Eversley, in Hampshire, Daniel Wadham, 21, of Bromley orchestrated the campaign which ran between 2001 and 2007, Winchester Crown Court heard.

Three other people - Gregg Avery, Natasha Avery and Daniel Amos - pleaded guilty to conspiracy to blackmail at Winchester Crown Court, Hampshire, last month.

Selby, 20, was described as one of three ‘foot soldiers’- along with Daniel Wadham, 21, and Daniel Amos, 22, - who researched victims for leaders of the blackmail campaign Gregg Avery, 41, Natasha Avery, 39, and Heather Nicholson, 41 to target.

The protestors, who were part of the group Stop Huntingdon Animal Cruelty (Shac), were sentenced to between four and 11 years at Winchester Crown Court today.

The court heard how the protesters carried out the six-year hate campaign - from 2001 to 2007 - against suppliers to the Cambridge-based animal testing company, painting words such as "puppy killer" and "scum" on homes and cars of workers and posting used sanitary towels to the victims with a note saying the sender had Aids.

Sentencing the activists, Mr Justice Butterfield called the campaign "urban terrorism" and a "relentless, sustained and merciless persecution" which had made the victims' lives "a living hell".

Prosecutors said the companies targeted included Astellas, F2 Chemicals, Biocair and GlaxoSmithKline, whose headquarters are in Brentford.