A man was prevented from making a dash to his dying uncle's side after a 23-hour flight when immigration officials decided he "looked suspicious".

Mark Troy, 42, had travelled from Australia to visit family in his native Brighton and spend a last three weeks with his uncle Mike Spicer, 66, who has terminal lung cancer.

But he was detained at Heathrow Airport when officers discovered he had just a few pounds in his wallet and was told he would not be allowed into Britain.

Mr Troy's aunt, Carol Spicer, 59, said: "We are just at a loss to understand why it has happened.

"He is such an honest boy and has never been in trouble with the law. He hasn't even had a parking ticket.

"There is no reason for them to deny him entry, especially as he has already lived here for many years and his mother is a citizen of the UK.

"The only reason he was given by the immigration officer was that he looked suspicious."

Mr Troy was born in Australia but lived in Brighton from the age of six. He moved Down Under to be near his dad when he was 30.

He was asked to give up his British passport in return for Australian citizenship but regularly returns to Brighton.

On Tuesday Mr Spicer, 66, was told that fluid had developed on his lungs and he needed an operation at Guy's Hospital in London.

Mr Troy's aunt said it could have been their last chance to spend time together.

Mrs Spicer, who is recovering from lymphoma, said: "This is probably the last time he will be able to see Mike.

"We have all been in tears.

My sister has been beside herself - she thought she had three weeks with him. He is her only child and she doesn't see him very often."

At first officers said Mr Troy had to be deported straight away but they relented and said he could visit his mother Sandy Troy at her home in Preston Park Avenue, Brighton, for one night if he left his passport at the airport.

During the short visit, he managed to have a tearful halfhour with his aunt and uncle.

Mrs Spicer, of Carden Crescent, Brighton, said there had been a problem last time he had visited because his bank balance was smaller than officials thought it should be.

She said she had telephoned to confirm he would be staying with family and he had then been waved through the gates.

She said: "This time he was not so lucky.

"He may not have much money but he doesn't need much to visit relatives.

"We are all so distressed about it."

A spokesman from the Home Office said he could not comment on individual cases.

He said: "General immigration laws state that it is up to the traveller to satisfy the immigration authorities that they meet the immigration rules and will be able to support themselves without recourse to using British taxpayers' funds."