He told police officers that he was in control and "knew my limit".

Yet, the 60-year-old driver clearly needed help as he staggered out of his flashy red Ferrari after having had three whiskeys.

He was one of 18 motorists netted in a ring-fencing operation - a strategic move to nab drink drivers - by the Traffic Police early yesterday morning.

Five roadblocks were set up simultaneously at Neil Road, Tanjong Pagar Road, Maxwell Road, Kreta Ayer Road and Cantonment Road, encircling popular watering holes in the area.

Officers sealed off all escape routes, even stationing themselves in the smaller lanes, and entrances and exits of public carparks.

Some 72 motorists were asked to take breathalyser tests in the four-hour operation. All 18 arrested were men aged between 28 and 60.

Police were on the look-out for telltale signs such as slurred speech and a strong smell of alcohol. Still, those hauled up insisted they did not have too much to drink.

One middle-aged woman, who was riding pillion on a motorbike, protested in Mandarin: "We just had a few beers," as her boyfriend was led to a black police van.

The highest figure clocked in the breathalyser tests was 78 micrograms of alcohol per 100ml of breath, more than twice the legal limit of 35 micrograms.

Senior Station Inspector Sanuwan Shaari, who supervised the operation, said motorists often falsely think they are in control of their vehicle after consuming what they believe to be a "small amount of alcohol".

Roadblocks were also set up at Tampines Road, Dunman Road and Fort Road.

Tougher enforcement such as yesterday's ring-fencing operation - the sixth since the police began using this tactic from January this year - has been credited for an 8 per cent drop this year in drink-driving arrests. So far this year, 3,552 drink drivers have been arrested, down from 4,010 last year.

This article was first published in The Straits Times on Dec 28, 2008.

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