She added that another taxi driver had witnessed the incident and contacted police.

It was later revealed that he had telephoned his brother to tell him he was going to commit suicide.

The man's body was found floating near Tai Lam at about 12.30pm, according to the spokeswoman.

'There was no suicide note and apparently he did not give his brother any reason for the decision to commit suicide,' she added.

Researchers and suicide counsellors have highlighted the rising trend in suicide jumps following the recent similar death of film star Leslie Cheung Kwok-wing.

In a statement on its Web site, the Hong Kong Jockey Club Centre for Suicide Research and Prevention voiced concern about the negative influence that suicides of famous figures could have.

'If public figures solve problems by committing suicide, people who are undergoing hardship may follow suit,' it said. However, it said that no research had been carried out on the subject.

Asha Balani, director of the Samaritans' multilingual suicide hot-line, said: 'With everything that is happening, we do have people calling in who are very confused about the way things are going.' She said people needed to offer each other support.

A 2000 study conducted by the Centre for Suicide Research and Prevention found the suicide rate had risen over the past two decades, and recorded that more men than women were likely to attempt to take their own lives. Jumping was the most common suicide method.

A 2001 report found charcoal burning was next on the list, and was especially common among middle-aged people.

The Samaritans' 24-hour suicide hotline number is 2896 0000.