JAKARTA/KUALA LUMPUR - Indonesia has sealed off plantations operated by 29 companies, including four subsidiaries of Malaysian groups and one Singaporean firm, after fires were detected in their concessions, the government said on Friday (Sept 13).

The legal measures against allegedly errant companies have been underway since last month.

Environment and forestry minister Siti Nurbaya Bakar said on Friday the government will prosecute a number of these companies as a deterrent to setting fires. Indonesia is struggling to curb spreading fires in Sumatra and Kalimantan and has faced criticism from Malaysia.

Ms Siti named the Singapore-affiliated company as Hutan Ketapang Industri, a West Kalimantan province-based rubber plantation subsidiary of another Indonesian company Sungai Menang, which is a wholly owned subsidiary of Indonesia's Sampoerna Agro. Singapore-based Sampoerna Agri Resources Pte Ltd owns two-thirds of Sampoerna Agro.

Sampoerna Agro was founded by the family of Indonesian billionaire Putera Sampoerna.

The four firms affiliated with Malaysian corporate groups operate in West Kalimantan and Riau provinces. Ms Siti named the companies as Sime Indo Agro (a unit of Sime Darby Plantation), Sukses Karya Sawit (a unit of IOI Corporation) and Rafi Kamajaya Abadi (a unit of TDM Bhd). The last one, operating in Riau, is Adei Plantation and Industry (a unit of Kuala Lumpur Kepong Group).

Ms Siti made her remarks in a media briefing after a three-hour coordination meeting in Jakarta that was chaired by Coordinating Minister of Political, Legal and Security Affairs Wiranto.

"We give no compromise to those that burn and cause fire," retired general Wiranto said in the same media briefing. "Our approach is, enforce the law hard and firm to create deterrent effect."

In response, Sime Darby Plantation (SDP) said on Friday that there had not been any action taken by the Indonesian authorities to seal off the operations of Sime Indo Agro (PT SIA).

SDP also said it was assisted by its Indonesian subsidiary in continually monitoring all its operation sites throughout the year, and that a recent fire that broke out on Sept 3 outside of PT SIA's operational area was in fact on land occupied by local communities. The fire was contained and the incident clarified to visiting authorities from the Indonesian Ministry of Environment and Forestry.

IOI Corporation also issued a statement late on Friday that its subsidiary had not received any official notification on the matter.

"PT SKS has been on high alert and has put in place measures to deal with the dry weather and the risk of fire," it said.

"We were able to quickly extinguish several small fires that have occurred over the last couple of months and have assisted other companies and villagers to respond to fires on our neighbouring lands."

The spouse of a scion of IOI Corporation is Malaysia's Energy, Science, Technology, Environment and Climate Change Minister Yeo Bee Yin, who has been sharply critical of Indonesia over transboundary haze.

Kuala Lumpur Kepong confirmed on Saturday (Sept 14) that a fire at P.T. Adei which the company said was successfully extinguished within a day. It said 4.25 hectares of its land had been sealed off for an investigation.

It said it is actively assisting the local authorities and surrounding communities to fight the fires while reiterated its zero burning policy and compliance with the Asean Policy on Zero Burning for all its plantations.

The head of Indonesia's Meteorology, Climatology and Geophysics Agency (BMKG), Dr Dwikorita Karnawati said Indonesia only detected transboundary haze originating in the country early on Friday, dismissing claims by Malaysia that haze from Indonesia has drifted to Malaysia for days.

"Only this morning at 8am that the haze started to enter (the area above) peninsular Malaysia. We have been monitoring every hour," Dr Dwikorita said on Friday, supporting her colleague, the environment minister, who has insisted there was only limited haze from Indonesia blowing over to Malaysia.

Adiplomatic row has erupted over the past days between both countries' environment ministers, centring on who is at fault for the hazy conditions.

On Thursday, Ms Yeo had cited data from the Asean Specialised Meteorological Centre (ASMC) that more than 1,600 hotspots had been detected in Kalimantan and Sumatra.

She tweeted on Friday: "All diplomatic channels exhausted to manage transboundary haze from Indonesia," in response to concerns that the government has not done enough to address the issue. She added Malaysia has reduced its own hotspots from 50 to fewer than 10 and that the ministry welcomes "constructive suggestions".

She also said the prolonged haze comes from hotspots in Indonesia that are on peatlands, making it harder to put out fires. However, Ms Yeo made no mention of any measures the Malaysian government would take against the Malaysian subsidiaries accused of having agricultural fires in their concessions in Sumatra and Kalimantan.

Primary Industries Minister Teresa Kok, who oversees cash crops such as palm oil, issued a statement on Friday to express concern over Indonesia's claim that Malaysian subsidiaries owned land where forest fires were reported.

Calling it a "serious accusation", Ms Kok said such allegations could lead to the cessation of these companies' certification status in Indonesia and Malaysia.

"Such action is also highly unwarranted since I remain concerned that the current accusation will play right into the hands of the anti-palm oil campaigners and both Indonesia and Malaysia as major palm oil producers could end up as the ultimate losers," she added.

As hazy conditions continue to plague Malaysians, Deputy Health Minister Lee Boon Chye said the ministry had recorded an increase of 30 to 40 per cent in haze-related illnesses. Clinics monitored by the health ministry over the last three weeks have seen more cases of respiratory tract infections, conjunctivitis and acute asthma attacks.

Local airports in affected areas in both countries have had a number of flights delayed because of the haze.

Indonesian Minister Wiranto on Friday also admitted the country is facing a bold challenge from traditional farmers, who have used slash-and-burn methods to clear land for generations.

"We have tried to find them help, asking corporations operating near them to lend them their heavy equipment to clear land. But we were overwhelmed by the huge number of these poor farmers," Mr Wiranto said. "Today, we discussed a way out. We will recruit these poor farmers as ground fire fighters so they will earn a living being fire fighters."

Indonesian weather forecasters say the dry spell will continue in Sumatra and Kalimantan until mid-October, with only minimal and intermittent rains until then.