BANGKOK - Thai police have said the bomb that exploded at Bangkok's Rajprasong Intersection was made of five kilogrammes of TNT explosive.
A source said the bomb was hidden under a roadside bench in front of the Erawan shrine.
The explosion had a radius of 40 metres, the source added.
The homemade bomb was detonated with an electronic circuit.
Nation TV reported that the death toll rose to 15, and that 77 people were injured.
The Red Cross Society issued an urgent plea for the people to donate blood Tuesday as a lot of blood supplies are needed for the victims of the explosion.
The bomb exploded at 6.55 pm.