Customs officers and the police have arrested five people believed to be involved in the smuggling of about 11,500 litres of diesel.

The Customs Department said that investigations were launched following information supplied by the Security Service.

It said Customs and police officers from the economic crimes unit monitored the movements of a number of people who were acting suspiciously in Sa Maison on Saturday evening.

At one point, the officers spotted a van approaching the quay. It stopped near a trawler, which had been berthed in Marsamxett.

Crew members appeared to be pumping fuel into large containers in the van.

Officers boarded the trawler and confirmed that fuel was being channelled from the vessel into tanks in the van using an electric pump, Customs said. More tanks were found in another van.

Five Maltese crew members, including the owner of the trawler, were arrested and 11,500 litres of diesel were seized.

Samples are being analysed.

The trawler and the two vans were also confiscated.