Bihar Train Disaster

On June 6, 1981, a passenger train travelling between Mansi and Saharsa, India, derailed while it was crossing a bridge spanning the Bagmati river and plunged into the river. The government places the official death toll at 268 plus another 300 missing, but some estimates put the death toll as high as 800.

http://en.academic.ru/dic.nsf/enwiki/892529