Nakhon Si Thammarat's Ron Phibun district police station superintendent Pol Col Prawit Janthabat and the State Railway of Thailand (SRT) staff has inspected the scene at Ron Phibum district where the cargo train derailed at around 1pm.
The train number 721 originated from Bangkok's Bang Sue station en route to Hat Yai. There was a total of 19 carriages - 17 containers, one locomotive and one passenger carriage which carried SRT staff.
All carriages derailed and were inclined on the right side of the track. The track and sleepers have damage around 100 metres in length.
There were two people injured from the accident, Mr Waedaoh Tehyor who was a driver and another one identified as Mr Kamron Kaewsasen. Both were sent to hospital but doctors said they were only slightly injured.
Chong Khao Rail Station chief Surapong Suthipan said the train has just left the station and was heading to Ron Phibun Station. The train entered tunnel for 300 metres and then derailed.
The SRT authorities went to investigate the cause of the accident but it was believed that an old track was possibly the cause of the derailing.
An engineer at Ron Phibun Station was waiting for the SRT's Mechanical Engineering Department to inspect the scene and plan restorations before the maintenance work could begin.
The southbound route was disrupted and the restoration work would need at least one week to finish and resume services.
Col Prawit said he estimated the accident has caused more than Bt100 million in damages.