An anti-reservoir campaigner in Steventon is offering a reward of £500 to help catch those responsible for tearing down poster boards and ripping up signs attacking Thames Water's plans.

Farmer Robert Tyrrell - who stands to lose 300 of his 630 acres of land if the huge reservoir is built between Abingdon and Wantage - is offering the reward for information leading to a court conviction. The police are investigating.

Mr Tyrrell said: "We are all very angry at this systematic campaign of vandalism targeting posters and signs in the village.

"People have gone to a lot of trouble and expense buying wooden stakes and boards. One large plastic sign that cost me £90 was sited on a fence outside the bakery. It was attacked by someone using a knife who cut out the lettering."

Mr Tyrrell's theory is that the attacks have been carried out by an adult and not young people.

He said: "I have a suspicion. The person may be in favour of the reservoir but I think it's more a case of bloody mind- edness.

"Whoever is responsible we want them caught and the campaign of vandalism stopped."

Signs on boards staked into the ground along Mr Tyrrell's land in Drayton Road have been attacked three times. Stakes have been uprooted and anti-reservoir signs smashed. Signs dotted along Hanney Road on Mr Tyrrell's land have not been touched.

He added: "We are all very angry at what's been going on. Whoever is responsible has been trespassing and causing criminal damage.

"It needs to be stopped and that's why I'm offering a reward so we can catch who is resp- onsible."

A large plastic sign hangs from fencing outside the entrance to the Old Farm House Bakery in Drayton Road owned by Rodney Bitmead.

He said: "It's very petty. A lot of people are very worried about the implications of a reservoir and are campaigning hard against it. The poster campaign highlights people's fears."

Carole Hooper - a member of one of the reservoir opposition groups Gard, Group Against Reservoir Development - said the campaign of vandalism and criminal damage was appalling.

She added: "Whoever is responsible is infringing people's right to express their opinions about the reservoir. This is a crude attempt to suppress people's views."