Indore-Rajendranagar Express derailed in Kanpur: 
Patna-bound Indore-Rajendranagar Express went off the track in Kanpur Dehat district of Uttar Pradesh in the early hours of Sunday. 
At least 121 people were killed and over 200 injured.The derailment was one of the worst rail accidents in the country in recent years.

Cause of derailment yet to be identified:
The cause of the derailment was not known, railway officials suspected rail fracture. There was no tampering with the track as the Sabarmati Express crossed the same track nine minutes earlier. It would have reported any fault.

How many Railway zones are there?
Following are the 16 railway zones of India:

Railway zones : Headquarters
1. Central Railway :Mumbai
2. Eastern Railway :Kolkata
3. Northern Railway :New Delhi
4. North Eastern Railway :Gorakhpur
5. Northeast Frontier Railway :Guwahati
6. Southern Railway :Chennai
7. South Central Railway :Secunderabad
8. South Eastern Railway :Kolkata
9. Western Railway :Mumbai
10. East Central Railway :Hajipur
11. East Coast Railway :Bhubaneswar
12. North Central RailwayAllahabad
13. North Western RailwayJaipur
14. South East Central RailwayBilaspur
15. South Western RailwayHubli
16. West Central RailwayJabalpur

The rail accident region draws the jurisdiction of Eastern Circle, Kolkata to hold the statutory enquiry and other needful proceedings.

About National Disaster Response Force:
The National Disaster Response Force (NDRF) is a specialised force constituted for the purpose of specialist response to a threatening disaster situation or disaster under the Disaster Management Act, 2005.

The "Apex Body for Disaster Management in India is the National Disaster Management Authority (NDMA). The Chairman of the NDMA is the Prime Minister. The responsibility for Disaster Management in India’s federal system is that of the State Government. The ‘nodal Ministry’ in the central government for management of natural disasters is the Ministry of Home Affairs (MHA).

When 'calamities of severe nature' occur, the Central Government is responsible for providing aid and assistance to the affected state, including deploying, at the State’s request, of Armed Forces, Central Paramilitary Forces, National Disaster Response Force (NDRF), and such communication, air and other assets, as are available and needed.