The attack tore apart cement sleepers and tracks for about 20 meters radius but fortunately no one was injured as there was no passing trains at the time of the attack.
Manop Muenpreecha, Tanyongmas station chief, said the attack affected six trains running to and from Sungai Kolok station.
Workers could not yet go to the scene to fix the damaged as they have to wait for soldiers to clear the area for their safety. Manop said the repair will spend about two days.
Meanwhile violence in another deep southern province of Yala has continued unabated with two people killed in a bomb attack in Bannang Sata district as the Muslim holy month of Ramadan draws to an end.
Many people had expected the situation during Ramadan to be more peaceful but such hopes were disappointed by the killing of Mahamayuding Puteh and Assuwan Yusoh and other attacks in the restive region.
Both men, who were active in fighting militants in the area, were riding a motorcycle on their way home from a mosque when the explosive detonated.
The attack took place at about 1am Sunday, with bomb squads having to wait until 9am before inspecting the scene near a bridge in the district.