Twenty Indonesian men who were arrested while fishing illegally in waters off North-Western Australia have been sentenced in a Northern Territory court.

The ABC reported earlier this month that a traditional owner and tour operator led Australian Border Force (ABF) personnel to four foreign fishing boats in the mangrove forests of Kuri Bay, about 220km north of Derby.

The ABF later confirmed that three of the four boats had been destroyed at sea. Twenty of the 33 fishermen were taken to mainland Australia for prosecution.

700 kg of sea cucumber, 4 kg of shark fins, 4 kg of sea urchin and 2,450 kg of salt were found on the boats.

The incident sparked a national debate about Australia’s maritime policy, with farmers highlighting the threat to biosecurity.

Eleven Indonesian men appeared in court in Darwin on Thursday, all pleading guilty to using a foreign boat to fish in territorial waters.

One fisherman, believed to be a captain, was sentenced to one month in prison, suspended for two years.

A second man was fined $300, while the other nine were fined $150.

All 11 individuals were issued disciplinary action, meaning they will face fines of $1,000 or $2,000 if they are found guilty of similar offenses in the next one to two years.

The remaining nine Indonesian men also appeared in court in Darwin on Friday.

Two men were fined $4,150, another $300, and the remaining six were all fined $150.

These nine men were also ordered to pay damages, with a possible fine of up to $2,000 if they reoffend within one to two years.

The ABF has been contacted for comment, particularly regarding whether the men have since been deported to Indonesia.