How the India Train Crash Unfolded

The New York Times; drone image via Reuters
The investigators of Train accident kills many people in India focused on the possibility that it was a fault in the electronic signaling system. This is how officials say disaster has unfolded.
first Two passenger trains approaching
At about 7 p.m. local time, the Coromandel Express passenger train approached from the north at about 80 mph. A second passenger train, the Yesvantpur-Howrah Superfast Express, arrived from the south at the same time.
2 Coromandel Express turns onto occupied tracks
The Coromandel Express turned onto an adjacent track where an idling freight train was loaded with iron ore. An Indian Railways official said that a problem with the signaling system was most likely the overall cause of the accident, although investigations are still underway.
3 First passenger train collides with cargo ship
Coromandel Express collided with a freight train. The cars in front of the Coromandel jumped off the tracks and formed a pile of rubble. More than 20 cars from the Coromandel derailed.
4 Second passenger train crashed
The derailed cars of the Coromandel Express collided with the second passenger train as it passed, causing the two carriages at the end of the second passenger train to derail.
The scene of the accident stretched for more than ten meters.
Source: Approximate positions of train carriages based on photos and videos from the scene.
The New York Times; satellite image of Airbus