Earlier this week, 16 plantation companies had their business licences suspended and three others were ordered to stop operations for good after a government investigation found that they were responsible for illegal fires that caused this year's transboundary haze crisis.

This is Indonesia's biggest clampdown on haze culprits, with several of the errant companies known to be suppliers to the country's two largest pulp and paper producers. Further announcements can be expected when investigations of other companies are completed.

The government is indeed taking a tough line, but it can still do better to show that it means business.

For instance, the Environment and Forestry Ministry stopped short of naming the errant companies, opting to give their initials instead. The exception was Bumi Mekar Hijau, which has committed repeated breaches and is now facing a 7.8 trillion rupiah (S$804 million) environmental damage lawsuit filed by the government. The company is reportedly a unit of Sinar Mas Group, which owns Asia Pulp and Paper, Indonesia's largest pulp and paper producer.

One of the companies named by its initials HSL is Hutani Sola Lestari, which supplied raw materials to Asia Pacific Resources International (April), the country's second-largest pulp and paper producer.

However, Sinar Mas, through a public relations agency, and April have denied any links or affiliations with the suspended companies.

There have been concerns, especially from green activists, that the two groups might try to distance themselves from the errant companies in order to avoid any possible civil as well as criminal lawsuits from the government.

If that is the case, the Indonesian government should come down hard on all companies and their true owners. And it should not shy away from naming - and shaming - the culprits.