Air ambulance fundraisers fear supporters could be misled by an appeal for clothes and jewellery.
Trading Standards have begun an investigation into leaflets which have been distributed to homes in the Portsmouth area, featuring the bold heading 'Air Ambulance Services'.
The leaflets include a picture of an air ambulance and a plea for 'urgent' donations of clothing.
But Hampshire and Isle of Wight Air Ambulance is worried that supporters may make donations in the mistaken belief that they are supporting the charity.
In fact, the company, which calls itself Ambulance Service (Trading Co Ltd), is a private firm based in Oxford and has no links with the air ambulance in Hampshire or elsewhere in the country.
Trading Standards in Oxford is investigating the company after air ambulance organisers in Hampshire and in Oxford put in complaints.
Sherie Williams Ellen, administration manager for Hampshire and Isle of Wight Air Ambulance, said: 'There is a picture of an air ambulance on the leaflet, so we fear people will be easily misled.
'If people think they are giving money to charity then we need to warn them. This is causing a great deal of distress .'
As well as asking for donations, the leaflets invite people to apply for a 'membership card' either by sending a text message costing 5 or calling a 1.50-a-minute helpline.
The internet address on the leaflet is for a website which refers to a sister company, Air Ambulance Service, and invites people to donate cash to help buy a 5m Eurocopter EC135 helicopter.
Both companies are registered to the same address in Bernwood Road, Bicester, Oxford, by 46-year-old Anthony Durkin.
Patrick Conafray, head of fundraising at Thames Valley and Chiltern Air Ambulance Trust, which covers Oxford, said: 'We have no link at all with the organisation. I think they are misleading the public and that charities are missing out. We have had Thames Valley Police look into this but they couldn't see that the company was doing anything wrong.'
Mr Durkin and Air Ambulance Service could not be reached on the telephone number provided on the leaflet, but the company e-mailed The News this statement: 'Air Ambulance Service is limited by guarantee, a not for profit company. Our trading partners work extremely hard on our behalf to raise funds from clothing collections. The profit, a minimum of 60 per tonne, goes towards helping people who are caught in difficult medical circumstances.'
Sarah Langley, interim deputy head of Trading Standards at Oxford County Council, said: 'I can confirm that we have received enquiries regarding charitable collections about a company based in Oxfordshire.
'We take all complaints seriously and will investigate any allegations of people being misled in relation to charitable donations. We advise people to always read the small print when making donations of goods or money, to ensure they are clear who the organisation is, what they are donating to and on what terms.'
Hampshire and Isle of Wight Air Ambulance provides air ambulance services in response to emergency calls.
On May 18 this year a 21-year-old man was airlifted to hospital after crashing a motorbike into a fence.
Jesse Palmer hit the iron fence in Forton recreation ground, off Forton Road, Gosport, and was taken by air ambulance to Southampton with serious injuries.
And in the same month an 18-month-old girl was rushed to hospital by air ambulance after she fell ill at the Funland amusement park on Hayling Island.
The toddler had a fit and stopped breathing. She was rushed to hospital and was later discharged.
The charity has undertaken over 2,260 missions since July 2007. For information go to: hiow-airambulance.org.uk
'THIS UNDERMINES OUR NEEDY CHARITIES'
Richard Thomson, The News' consumer expert and a former Trading Standards manager said the company's leaflets undermine charities who rely on donations to run.
He said: 'Trading Standards will be looking to see if any of their claims are true.'
He is urging residents not to be fooled by leaflets that come through their doors, appearing to be from a charity.
He said: 'If something is from a genuine charity it will have a charity number. People can put the number into a website search engine and if it is a charity it will come up.'
Trading Standards is now investigating the company, however Mr Thomson says there may also be legal issues.
He said: 'This is not necessarily a crime, however there is a constraint in law for "passing off".
'This is to do with copying someone else's mantra as closely as you can so that you can cash in. Most of these things are protected by copyright. And the first thing that is crossing my mind is that the literature is a pastiche of someone else.
'But most charities cannot spend money on taking people to court as that is not what their money is for.
'This is definitely a grey area.'
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