Minister of State for Railways R Velu, who visited the accident site near here, said a high-level probe into the accident would be conducted by the Commissioner of Railway Safety and the report would be submitted within seven days.

He said nine persons have been killed in the mishap that took place on Friday when the Chennai-bound Coromandel Express from Howrah derailed while changing tracks near Bhubaneswar.

"Nine bodies have been recovered from the site. A higher death toll was anticipated earlier on the basis of preliminary assessment," Velu told reporters.

He said only 45 of the injured passengers were admitted to different hospitals where the condition of six was stated to be critical. Most of the injured were discharged after first aid, he said.

Earlier, railway officials had put the toll at 16 passengers killed and 161 injured. Velu said the men and machinery of the Railways and other agencies were working on a war-footing to clear the tracks to restore normal traffic on the important route within 48 hours.

About possible reasons for the mishap, Velu said it could be technical, human error or any other factor. "At this stage it is difficult to guess the exact cause. We are reviewing the entire matter."

Meanwhile, over 700 passengers were sent by a special relief train to Chennai from the accident site. The passengers on board the special relief train were bound for various places in Tamil Nadu and Andhra Pradesh, railway sources said.

After taking stock of the situation at the accident site, Velu also went to the Jajpur hospital and enquired about the condition of the injured.

A sum of Rs 5,000 each was handed over to the injured and railway officials have been asked to make arrangements for their treatment, the sources said.

Besides Velu, Railway Board chairman S S Khurana and other senior officials were monitoring the massive operation undertaken to clear the track. It was likely to pick up further momentum during the day.