By Shoon Naing and Artorn Pookasook SISAKET, Thailand (Reuters) -Fighting on the Thai-Cambodian border extended into a third day and new flashpoints emerged on Saturday as both sides said they had acted in self-defence in the border dispute and called on the other to cease fighting and start negotiations.

Thailand and Cambodia exchanged fire along their disputed border for a second day on Friday, officials from both countries said, with more than a dozen people reported killed and more than 135,000 civilians evacuated.