Kuala Lumpur Kepong Bhd, the owner of PT Adei Plantation Industry which Indonesia has named as being one of four Malaysian-linked firms responsible for forest fires, said it is cooperating with Indonesian authorities on the matter.

"At present, 4.25ha including an isolation area has been sealed off for on-going investigations.

"PT Adei will continue to give full support to Indonesian Ministry of Environment and Forestry and all relevant authorities to assist in the on-going investigation of the case," it said in a statement today.

KLK said fires did occur on it subsidiary company's estate and that it had worked to extinguish them.

"KLK regrettably confirms the occurrence of a hotspot area which affected 2.8ha in the 14,400ha-estate managed by PT Adei. The hotspot occurred during an unusually acute dry spell where rain was recorded only two days out of the last 60 days.

"This hotspot was successfully extinguished on the same day through the effort of our own 120 firefighting personnel aided by 11 excavators and pumps.

"As a safeguard measure, water was continually doused throughout the night to ensure the affected area remained wet and to avoid a recurrence," it said.

KLK said it acknowledges the Indonesian government's seriousness in tackling the "complex issue" and it fully supports the efforts.

"KLK wishes to reiterate its zero-burning policy and is in full compliance with the Asean policy on zero burning for all its plantations operations.

"KLK is serious in its fire-fighting agenda and has fully equipped fire-fighting teams in its estates.

"The team attends fire-fighting training yearly and practises strict patrolling system which includes setting up fire towers to inform ground patrol of any occurrence of fire," it said.

Hundreds of hotspots across Indonesia have been blamed for the haze blanketing Malaysia.

The other three Malaysian-linked companies implicated by the Indonesian government are Sukses Karya Sawit, a unit of IOI Corporation, Sime Indo Agro, a unit Sime Darby Plantation and Terengganu-owned TDM Berhad.

Sime Darby Plantations and IOI Corporation Bhd have refuted claims by Indonesia that their plantations run by subsidiaries were sealed off due to fires.