Kamayani Express enroute to Varanasi from Mumbai derailed near Harda, about 160 km from Bhopal, around 11.45 PM while the Janata Express derailed around the same time.
"There was water on tracks and the bridge was submerged. So the last bogies of Kamayani Express got derailed. Simultaneously, on the other track the engines and coaches of the Janata Express also got derailed," Railway spokesperson Anil Saxena said.
He said that some casualties are feared.
Harda Collector Rajnish Shrivastava told Press Trust of India that derailment took place near Khirkiya and Harda station on Machak river.
Some bogies and engines of both the trains are in water, he said.
Hoshangabad Division Commissioner V K Batham said that Janata Express also derailed at the same spot on its way to Mumbai from Jabalpur.
A relief train carrying collector, SP, doctors and other railway staff is on the way, he said.
"Rushing emergency medical & other relief personnel to spot. darkness, water creating hurdles but ordered all possible help. Trying our best (sic), " Railway Minister Suresh Prabhu tweeted.
He said efforts were underway to pull back the bogies.
"We r gearing up all possible help on basis of info, will not spare any efforts," he tweeted.
He said Railway administration and MP government are working together to rescue passengers of Kamyani express accident. He further said that GM, DRM,RPF and medical staff have been directed to rush to the spot.