The 12 victims comprise of seven males and five females who were killed by the ensuing fire that consumed their vehicles after the collision.
The victims were taken to Ananda Hospital and Bekasi Regional Public Hospital (RSUD).
It was previously confirmed that eight people died in the accident.
Motorcycle riders can reduce the risk of accidents and higher level of damages it causes.
Four people were confirmed dead in a road accident in Balikpapan, East Kalimantan, when a truck that allegedly encountered brake failure hit dozens of vehicles that were stopping at a red light.
