Indonesian police have busted a syndicate which, for five months, smuggled stolen Malaysian cars into Batam by ship through Singapore.

Six Malaysians and three Indonesians have been arrested for their part in the ring, which pulled off the thefts and smuggling operations between last November and March this year.

No arrests have been made of those who may have run the operations here.

The Indonesian police have also found 40 vehicles, reported stolen by their owners from Johor Baru to Penang, in a Batam warehouse.

Referring to the bust in April, Riau Islands? police criminal investigation chief Basaria Panjaitan said: "It's the biggest seizure of stolen cars involving three countries - a transnational crime."

The cars, which are at least four years old, are valued at 100 million rupiah (S$17,000) each in Indonesia.

The syndicate's plan was to have them resprayed, passed off as new and sold for three times that amount, added Senior Commissioner Basaria.

Mr Eric Khoo, the director of Singapore car exporter Car Instinct, noted that in many parts of the world, cars with a body value of $17,000 were typically five- to six-year-old high-end makes such as Mercedes-Benzes, BMWs and Toyota Hiluxes.

More than a dozen stolen cars were Toyota Hiluxes, which cost $80,000 to $90,000 when new here, taxes included.

The Malaysian police have been informed about the case, and all the stolen vehicles will be returned to their owners in two months when investigations are completed.

Ms Basaria explained how the syndicate worked: Its members would drive the stolen vehicles across the Tuas Second Link to Singapore and into waiting containers at Jurong Port.

Falsely declared in Customs paperwork as furniture or other legal items, the cars - which include models like the Toyota Wish and Nissan Murano - would then leave Jurong for Batam's Batu Ampar port.

The export documents all bore details of each car's model and year of manufacture, but letterheads were of non-existent Singapore car export firms or had wrong addresses, said Ms Basaria.

A Straits Times check with the Accounting and Corporate Regulatory Authority (Acra) confirmed that one such 'car export' firm, KB Auto Trading, did not exist.

Another firm, Yang Guang Enterprise, was listed in export papers as having an Owen Road address. A check with Acra found a company with this name - but it was in Toh Guan Road East and in the business of renovation and cleaning services.

When The Straits Times visited that address, it found a car-grooming shop, ProSpeed Specialist. Director Thomas Ong said when Indonesian embassy officials dropped by last month, he told them he knew nothing about the car smuggling, and that his address had been misused.

Singapore Customs said exports of trade goods must be covered by a Customs permit.

The clearance and inspection of goods at the checkpoints, however, are handled by the Immigration and Checkpoints Authority.

But traders and security experts say it is near impossible to inspect all containers, which run in the millions, passing through Singapore each year.

Meanwhile, enforcement action in Batam has resulted in the arrests of three directors from two Batam car-import firms. They face jail terms of up to four years if convicted.