Police say thieves often identify patterns in car parking

They say people who come into the city centre to work and use off-street parking for long periods are particularly vulnerable.

A poster campaign has been launched to warn drivers of the risk, with the slogan: "Don't make a present of your property."

Constable Gail Haddock of the Crime Prevention Unit appealed for motorists to conceal any valuables and ensure their vehicles were locked and secured.

Thieves can very often identify a pattern Gail Haddock PSNI

"Cars parked by workers on the street from early morning until teatime can be particularly vulnerable," she said.

"They are left unattended for long periods and thieves can very often identify a pattern."

Police said the posters would be displayed in different areas for short periods of time.

They said the campaign's effectiveness would be assessed by studying crime figures before and after their display.

Figures published last April by the government showed a sizeable drop in the number of cars stolen last year - a drop of almost 2,500 cars stolen in 2003 compared to 2002.

South Belfast showed the biggest improvement with the numbers of cars stolen cut by almost half.