A father spent £10,000 on private detectives after police failed to track down the thug who killed his daughter ’ s kitten with an air rifle . Neil Tregarthen devoted six weeks to gathering information for a 15-page report that named their prime suspect – but officers dismissed it as ‘ rumour and speculation ’ and abandoned the case . Yesterday the millionaire former business owner – who posed as an angler at one stage to spy on youths he believed were responsible – criticised the police investigation as ‘ totally impotent ’ . Scroll down for video . Neil Tregarthen spent £10,000 on a private investigator after his daughter 's cat , Farah , was shot by an air rifle . He and the private eyes identified several members of a local gang that posted Facebook pages of themselves injuring animals , and had criminal records for air rifle related offences . But police refused to bring a prosecution because of ‘ lack of evidence ’ for an attack that condemned Farah the kitten to a slow , agonising death . Mr Tregarthen ’ s daughter Aylish was horrified to find Farah lying in a pool of blood after limping home wounded and crippled with pain last September . The 24-year-old medical student and her father took the kitten to a vet but she suffered ‘ a very long , painful , lingering death ’ from a ruptured bowel and blood poisoning , finally passing away on the operating table , Mr Tregarthen said . When police told him there was not enough evidence to pursue the case he hired the detective firm and offered a £1,000 reward to catch the killer . They distributed flyers and set up a phone line for people to give information . It quickly became clear there had been a string of air rifle attacks near where Aylish lives in Exeter , Devon . ‘ We narrowed it down to four youths , so we set about doing surveillance work , ’ Mr Tregarthen said . ‘ We would camp out on the river pretending to be fishing . We surveyed certain areas by pretending to be members of the public . Ideally we needed to witness an incident , but that never happened . We found a witness who claimed he had witnessed our main suspect shooting another cat. ’ The kitten , pictured right with one of the family 's other pets , died despite extensive treatment at the vets . Mr Tregarthen is offering £1,000 to anyone with information which could lead to Farah 's killer . The kitten was shot near her owner 's home in Exeter . Exeter-based Focus Investigations , whose staff includes ex-police officers , said the person responsible had ‘ an obvious sociopathic nature ’ . Mr Tregarthen , 56 , added : ‘ We compiled all the information we had , and presented it to the police . We did 85 per cent of the work – then Devon and Cornwall Police would not even go and knock on a couple of doors . Using an air rifle to shoot cats is illegal , and should be treated as such. ’ Mr Tregarthen , who lives in a luxury house in Truro , Cornwall , said of the cost of his own investigation : ‘ I would pay double that if I thought it would stop this sort of behaviour . ' I know I am in a fortunate position to be able to do so , but I think it is money well spent . It ’ s about society fighting back. ’ Mr Tregarthen enlisted the help of private investigators Focus ( offices pictured above ) to help find Farah 's killer . The animal is likely to have been playing in the garden when killed , Mr Tregarthen said . She returned to Miss Tregarthen 's house wounded . His daughter said : ‘ I feel like there is no justification for not investigating something that is illegal . We sympathise with the budget cuts – they have limited time and resources , which is why we chose to investigate it . But to still have the same response is very disappointing. ’ Devon and Cornwall Police neighbourhood beat manager Steve Parsons said : ‘ We investigated this crime fully . As for the investigation report , I have examined this and it is packed with rumour and speculation , not evidence . ‘ However , on the back of this , officers did make further inquiries in the area which also turned out to be fruitless . I am confident we have done everything possible in investigating this case. ’ Mr Tregarthen said police were 'impotent ' in their investigations into who killed the cat , pictured above in a red collar . Mr Tregarthen lives in a plush £3million home in Truro , Cornwall ( above ) . His daughter is studying medicine in Exeter .
Neil Tregarthen hired private investigators to look into the animal 's death . Claimed local police in Exeter had been 'impotent ' in their inquiries . The father of one put together a report which named a potential suspect . But officers dismissed it as 'packed with rumour and speculation ' Farah the kitten returned to owner 's house wounded and bleeding to death .