Judgment adds all contractors who supply any goods or services to the university as a new category of "protected persons" against animal rights extremists.

The University of Oxford has been granted a new injunction by the High Court to combat animal rights extremists.

The order was made by Mr Justice Holland today and replaces earlier rulings obtained by the university by extending the groups of people given legal protection.

The latest judgment has added all contractors who supply any goods or services to the collegiate University as a new category of 'protected persons'. Previously staff, students, alumni and contractors working on the biomedical research building were covered.

The 'exclusion zone' - the area where protesters are prohibited from entering except to attend Thursday or other permitted demonstrations - has also been increased by the High Court.

The area has now been extended further along South Parks Road to St Cross Road and further down Mansfield Road.

The court has also recognised the disruption and distress caused by protesters using megaphones, klaxons, sirens, drums, whistles and other noise amplification devices within the exclusion zone. Restrictions have now been placed on the use of such devices by animal rights protesters.

Mr Justice Holland's ruling banned all noise amplification devices within the exclusion zone, along Mansfield Road and along St Cross Road. The order continues to provide those opposed to the building of the new biomedical research facility with the opportunity to hold weekly demonstrations close to the site every Thursday. Protesters will still be able to organise larger, national demonstrations in the city at other times with the appropriate authority from the police.

Dr Julie Maxton, Registrar of the University of Oxford, said: 'Today's judgement represents a significant advance for the cause of legitimate and essential scientific research at Oxford University. We all have the right to work and study in a safe and peaceful environment, free from threat, intimidation and disruption. That right is what the court has acknowledged today.

'This ruling extends legal protection from such unlawful behaviour to a wider range of people. It also offers a welcome measure of relief to many members of the University who have been subjected to unjustifiable harassment and distress.

'We acknowledge that some individuals and groups are opposed to the building of the University's new biomedical facility and to the potentially life-saving research to be carried out there. As a University deeply committed to freedom of speech, we fully recognise the right of such individuals and groups to express their views within the framework of the law. The judgement protects that right, while making it clear that it cannot be used as a cloak for unlawful activity and behaviour.

'We will wish to keep under review the operation of the new ruling and its impact on those it is intended to protect and those it is intended to restrain.'

The injunction also states that protesters should not picket or demonstrate within 100 yards of the residence of any protected person, anywhere in the country. It also makes it an offence for an animal rights protester to try to identify any vehicle entering or leaving the exclusion zone.

Mr Justice Holland also indicated that the injunction should be brought back to the High Court periodically for review, or earlier in light of any new evidence.

A copy of the Order will be available on the University's Biomedical Research website at: http://www.admin.ox.ac.uk/biomed/