A freight train derailed near the Deparja crossing near Mehrabpur in Naushahro Feroze city of Sindh, disrupting railway operations, sources said on Monday.
According to officials, 10 bogies of the train heading to Punjab were involved in the accident, with more than five bogies overturning and some derailing.
The incident has completely blocked both the up and down railway tracks.
A relief train has been dispatched from Rohri to clear the track and restore traffic.
Railway authorities said it may take eight to ten hours to clear the tracks.
Meanwhile, trains on both up and down lines are being held at different stations, causing inconvenience for passengers.