No one was injured and a suspect was arrested.
Arsonists set fire to the Para rubber wood-processing plant of Chairat Parawood Co on Raman-Taloh Halor Road in Kayu Borkoh sub-district of Raman district caught fire at about 3.30am on Friday. The place is 1.3 kilometres from Raman police station and the Raman district office.
At least 10 fire engines were deployed to fight the blaze, which spread quickly and fiercely through the timber stored on the premises.
Firefighters finally brought it under control about 7.30am, but the plant was mostly burned out. The damage was estimated at 10 million baht.
Witnesses said five attackers climbed over the fence around the plant, captured the security guard and tied his hands and feet.
Then they set the premises ablaze, fired two threatening shots and escaped. Tyre spikes were scattered on Raman-Ban Asong Road to obstruct any pursuit.
Banners with messages threatening Panu Uthairat, the new secretary-general of the Southern Border Provinces Administrative Centre (SBPAC), were found in the three insurgency hit southern border provinces of Yala, Pattani and Narathiwat on Friday morning.
They were seen in Raman district of Yala, in Muang Pattani, Yarang, Mae Lan and Khok Pho districts of Pattani, and in Muang Narathiwat, Yi-ngo and Chanae districts of Narathiwat province.
A 21-year-old man identified as Iraham Pohno was arrested while hanging such a sign in Ban Paree village of Chanae sub-district. He is a resident of Chanae's Chang Phuak sub-district. Authorities were questioning him about his associates.
The signs warn there could be "incidents upon the return of Mr Panu".
Mr Panu, who was the first secretary-general of the SBPAC, said he hoped the situation in the far South would improve following the National Council for Peace and Order's restructuring of agencies responsible for solving the problems in the region.
The SBPAC was moved from being under the jurisdiction of the prime minister to being answerable to the southern office of the Internal Security Operations Command. The commander of the 4th Army directs the southern office.
NCPO chief Gen Prayuth Chan-ocha has also taken overall control of the far South.
Mr Panu said the violence is declining in the far South.