A DISGRUNTLED farmer launched a year-long hate campaign against a couple who had outbid him to buy a fish farm, a court heard yesterday.

Police who raided his home on the outskirts of Durham City after the couple's 12-year-old son received rat poison through the post discovered a cache of explosives, timers and bomb-making equipment, Newcastle Crown Court was told.

Robert Walker, 50, of New Ivesley Farm, near Esh Winning, who was pipped at the post in the purchase of the fishery by Sidney and Margaret Boulter, tried to drive them from the land through intimidation, it is claimed.

The litany of harassment included leaflets warning of paedophiles at the farm, oil thrown on to a fish lake and the rat poison sent through the post.

During that time, Mr Walker was said to have continued to offer to take the property off the hands of the "terrified" owners.

Mr Walker denies one count of harassment against Mr Boulter and a separate count against his wife between April and September 2000. He has also denies illegally possessing explosives.

The court heard how the saga began when Mr Walker made a £190,000 bid for Oakbank Fisheries near Longtown, Cumbria, but then tried to beat the price down by claiming the land was riddled with defects.

Christopher Knox, prosecuting, said that between July and September 1999 a position was reached whereby the price was reduced to £175,000 - but the vendors became "fed up with what they perceived as his messing about" and withdrew.

When they accepted an offer of £150,000 from the Boulters, Mr Walker began a campaign to scare the family away, the jury was told.

Calls were made to the couple's solicitor trying to put them off buying the property, but on April 5, 2000, contracts were exchanged.

Mr Walker's reaction was "prompt". On April 7, he contacted Carlisle police to claim a paedophile was working at the farm - a claim police concluded was unfounded.

On June 5, Mrs Boulter found a leaflet propped up on a drum of diesel at the premises. It read: "We the people of Longtown do not want your sort on our doorstep. Get out now while you still . . ."

Mr Knox said: "Lo and behold, the day after the note appeared, Mr Walker contacted the Boulters' solicitor offering to buy the premises."

The next day, diesel was found poured into a lake where fish were stocked. By June 15, leaflets had been posted to commercial angling businesses in Cumbria, and were stuck to lampposts and thrown out of a passing car.

One read: "Save our school kids. Paedophiles are operating at Oakbank Fisheries. You know what to do!!! Encourage them to close down. . ."

SOS was later painted on approach roads and a leaflet mentioning the "explosive art for the pyrotechnician" was found.

On July 11, a week after the Boulters' son appeared in a local newspaper for winning a fishing competition, a packet containing rat poison was sent to him. A week later, Mr Walker made the Boulters yet another offer for the premises, the court heard.

When police raided his farm, they found a pipe bomb, four modified flash units, gun powder, a length of copper pipe, a modified torch, milk cartons containing petrol, and an alarm clock made into a timing device.

Mr Knox said: "Here is a man who engaged in this campaign of harassment frightening these people into thinking violence would be used against them."

He said the pipe bomb was usually found in a "terrorist context" and was a "crude but effective weapon".

Mr Walker told police he knew nothing of the pipe bomb, and claimed the pyrotechnics were to put on displays for his wife, and everything else had a legitimate purpose.

The trial continues.