SINGAPORE - The police have arrested four more men, aged between 25 and 58, for their suspected involvement in an illegal transaction of marine gas oil at sea off northern Tuas.

This brings the total number of people involved in the case to seven, after three men who were members of a foreign-registered vessel were nabbed by the Police Coast Guard on Sunday (Aug 26).

The trio - aged between 22 and 30 - had been arrested in a joint operation with the Maritime and Port Authority, and were charged in court on Tuesday.

The foreign-registered work boat, as well as $3,501 in cash, were seized for investigations.

In a statement on Wednesday, the police said the four men - who were from a Singapore-registered vessel - were arrested after follow-up investigations.

They allegedly stole the marine gas oil and were selling it to the foreign-registered vessel.

Cash amounting to $630 was seized.

Related Story 3 men arrested for suspected involvement in illegal transaction of marine gas oil off Tuas

If convicted of criminal breach of trust, the four could be jailed up to 15 years each and fined.