The Gangmasters Licensing Authority has launched a four-week radio advertising campaign in Polish and Portuguese to encourage workers in the agriculture, horticulture and food/drink processing and packaging industries to report illegal or exploitative practices.

The GLA's advertising campaign will also remind labour providers that they have until 1 October to get a licence. If they fail to do so, they will be committing an offence which carries a penalty of up to 10 years' imprisonment and a fine of up to £5,000.

GLA chief executive Mike Wilson said: "Through this campaign we want to build up trust with the workers who will be protected by the GLA, so that they have the confidence to report the illegal gangmasters."

The GLA says its enforcement officers are now operating in England, Wales, Scotland and Northern Ireland, gathering and following up intelligence. Once an offence become active, the officers will investigate, interview and gather evidence. They will also enter relevant premises, by warrant if necessary.

All of this information will influence licensing decisions and provide the basis for prosecutions if illegal practices are found.