About 100,000 Iraqi civilians have died since the US-led invasion, according to a study by Iraqi and US public health experts.

The study, carried out in 33 neighbourhoods of Iraq and published on the Web site of the Lancet medical journal, shows that violence is now the leading cause of death in the country.

Earlier, most people died of heart attacks, strokes and chronic illness. The risk of a violent death is now 58 times higher than it was before the invasion.

Les Roberts of the Johns Hopkins Bloomberg School of Public Health in Baltimore led the research. Five of the six Iraqi interviewers who went to the 988 households in the survey were doctors.

Householders were asked about births and deaths in the 14.6 months before the March 2003 invasion, and births and deaths in the 17.8 months afterwards.