A photo of the crash is shown above.
One of the trains apparently failed to stop at a red light and hit the other at high speed.
The train line involved is fitted with a security system designed to halt trains automatically at a stop sign.
However one of the trains was not equipped with the system, according to Marc Descheemaecker, a senior official for the SNCB national rail service.
The driver of one of the trains was killed in the crash. Investigators are waiting to interview the surviving driver who was badly injured in the crash.
Link