Three more bodies were retrieved on Thursday from the derailed Golconda Express taking the death toll in Wednesday's mishap to 21.
Hectic efforts were also on to restore rail traffic in the section.
"Three more bodies have been retrieved -- two of them crushed under the engine and another from the mutilated coach," General Manager of South Central Railway Stanley Babu said.
The engine and two bogies of Secunderabad-bound Golconda Express had jumped off the tracks and fell from an overbridge on to a road below, hitting the traffic below.
Evading a reply on the cause of the accident and fears over safety measures, Babu said the Railway Safety Commission was conducting a full-fledged inquiry into the mishap.
"We will give you details only after the inquiry report is submitted," he said.
After painstaking efforts, hampered by incessant rains, rescue teams lifted the mangled engine using heavy-duty cranes.
Babu said the relatives of each of the deceased would be paid an ex-gratia of Rs 100,000 by evening after proper verification, while Rs 15,000 to each was paid to 16 injured passengers, who were now undergoing treatment at a government hospital.
