GROWING numbers of Scots teenagers are taking up smoking, new research shows.

A study found a third of 16-24-year-olds are smokers - a rise of 5% in the past three years.

The percentage of young people smoking fell from 31% to 25% between 1999 and 2004, but soared to 30% in 2007.

The study found more young women aged 16-19 than young men are lighting up, but in the 20-24 age group male rates exceed female rates.

Researchers also found specific groups in the population have much higher smoking rates than average.

Four in five young offenders smoke - 2000 young adults - and two-thirds of care leavers.

Young people who work in retail, hospitality and the construction industry are also more likely to smoke.

More than half of young adult smokers have jobs (51%), with 30% jobless, 16% in further or higher education and 3% at school.

The study was carried out by NHS Health Scotland and the Scottish Public Health Observatory.

The Scottish Government has set a target to reduce the smoking rate of young adults to 23% by 2012.

A range of measures aimed at discouraging children from taking up smoking are under discussion, including removing cigarettes from open display in shops. England and Wales have already announced a ban.

Public Health Minister Shona Robison said: "Significant progress has been made in recent years to shift cultural attitudes to smoking, but this report clearly demonstrates that firm action needs to continue if we are to succeed in our desire to make Scotland smoke-free.

"In May we signalled our intention - among a range of measures aimed at preventing smoking among children and young people - to remove cigarettes from open display in shops."

MSP Kenneth Gibson is also calling for a ban on cigarette vending machines, after research found one in 10 underage smokers buys cigarettes illegally from the machines.

David Gordon, of NHS Health Scotland, said: "Meeting the 2012 target will require sustained and radical population-wide action."