British tax officials are investigating whether some of Britain's top celebrities took advantage of a charity donation scheme for personal gain.

Celebrities, including comedians Angus Deayton and David Baddiel, allegedly claimed large amounts in tax relief after donating stock shares to charities, the Sunday Times of London said, sometimes making more than the charities. Her Majesty's Revenue and Customs office launched an investigation into the practice.

Both Deayton and Baddiel denied wrongdoing, the Times said.

The HMRC office is investigating whether stock prices were manipulated to increase their value before being given to the charities.

Investigators said celebrities used the tax refund practice to make money from the stock flotation -- a stock offering -- of Poly Information, a small voice-recognition firm with about $230,000 in annual revenue, the Times reported.

Investigators said the 10 million shares of Poly Information stock Deayton bought quadrupled in value on flotation. He then donated 9 million shares to Islington Angel Charitable Trust, which he established, the Times said.