Yesterday, the petrol station was serving more J-plate vehicles than S-plate ones. The town's restaurant owners, retailers and cabbies have also noticed slacker business over the past few weekends.

Three words explain this: Mas Selamat Kastari.

Petrol station cashier Rozana Mohd Din, 33, is certain that the heightened security following the escape of the 48-year-old Jemaah Islamiah terrorist is responsible for this.

The more thorough checks on travellers and vehicles passing through the Woodlands Checkpoint are keeping Singaporeans away.

Ms Rozana noted that the petrol station usually serves 100 Singapore cars on weekdays and 150 on weekends. She is seeing only half of that number now. 'It's so unfair that businesses here have to suffer because of one man,' she said.

Other JB businesses complained that takings had fallen by 20 to 75per cent. All expect this month to go down as one of the worst sales months in recent times.

When The Straits Times visited JB town centre yesterday, business at the food stalls appeared brisk. But stallholders said the customers were not quite as free spending as Singaporeans.

Hawker Ahmed Abdullah, 45, who sells Indian food, said: 'Singapore customers may come only once a week, but they spend a lot. They come with friends and order whatever they fancy on the menu.

'They can spend RM30 (S$13) in one sitting. Malaysian customers take a long time to decide - and when they do, they spend RM3.'

At City Square, cash registers were not ringing despite the ongoing sale. Boutique assistant Lim Kim Moi, 35, whose boss had chided her for the poor sales, said: 'Now, I am forced to be pushy and get the Malaysian customers to buy.'

Taxi drivers, too, were cooling their heels in a long line of cabs outside the JB checkpoint yesterday.

Cabby Masdan Rudin, 35, said: 'On weekends, I usually take 15 Singaporeans to Senai airport and bus terminals. Now, it's down to 10.'

The worst thing for these businesses is not knowing when the jams will ease and the crowds return.

DVD seller W.Y. Tan, who has suffered a 75 per cent drop in takings, said: 'If it's going to be like this for the next two months, I might have to start selling char kway teow.'

arlina@sph.com.sg