Expressing shock and grief at the tragic train accident in Odisha, opposition leaders on Saturday stressed the importance of prioritising the safety of passengers by railways, while there were also demands to fix accountability and for the resignation of Railway Minister Ashwini Vaishnaw.

The accident involving three trains in Odisha's Balasore district killed at least 261 people and injured more than 900, in one of the worst railway tragedies in the country.

The Congress said the "horrendous" train accident in Odisha reinforces why safety should always be the foremost priority in the functioning of the rail network and asserted that there are many questions to ask of Prime Minister Narendra Modi and Railway Minister Vaishnaw but those can wait as the immediate task was of rescue and relief.

In a statement, Kharge said, "At this moment of a grave national tragedy on account of the terrible train disaster in Odisha, I have instructed the entire Congress party organisation to extend all possible help." A number of Congress leaders from different states have either already reached or will soon be reaching Balasore, he said and extended heartfelt condolences to the bereaved families.

"We have many questions to ask of the prime minister and the railway minister but those can wait since the immediate task is of rescue and relief," Kharge said.

Congress general secretary in-charge communications Jairam Ramesh said the train accident in Odisha is truly horrendous and is a matter of the greatest anguish.

"It reinforces why SAFETY should always be the foremost priority in the functioning of the rail network. There are many legitimate questions that need to be raised but that should wait till tomorrow," Ramesh tweeted.

West Bengal Chief Minister Mamata Banerjee, who is a former railway minister twice and flew to the accident site on Saturday afternoon, demanded a proper investigation.

“This is the biggest train accident of this century and a proper investigation must be conducted,” the Trinamool Congress (TMC) chief told reporters.

"Something must be behind this. The truth must come out. Why didn't the anti-collision system work?" Banerjee said TMC spokesperson Saket Gokhale said there were serious questions about the accident that needed to be answered.

"My fervent prayers for those affected & their families. ...That an alleged signalling failure led to 3 trains crashing is shocking beyond belief. There are serious questions which need answering," Gokhale tweeted.

The railways have said that "Kavach" - the automatic train protection system was not available on the route where the accident occurred on Friday evening.

CPI(ML) general secretary Dipankar Bhattacharya too raised the same question. "Do we no longer have any signalling and safety system in Indian railways? Or will such terrible tragedies become the new normal for rail travel in India? We owe an answer to the victims and to the families who lost their near and dear ones in this mishap," he said in a tweet.

The CPI and RJD demanded that Railway Minister Ashwini Vaishnaw resign over the incident.

"Government concentrates only on luxury trains. Trains and tracks of common people are neglected. Orissa deaths are the result of it. Rail minister should resign," CPI MP Binoy Viswam said in a tweet.

Some Congress leaders also called for Vaishnaw's resignation.

Tagging a tweet by Vaishnaw on ex-gratia compensation to victims of the accident, Congress' MP from Odisha Saptagiri Ulaka said, "You should resign first." Ask some person to investigate the reason for this mishap and do course corrections, as well as ensure support to the injured, the MP said.

"Avoid such insensitive tweets at times of pain, anger and deep personal loss," Ulaka said.

The accident highlights the infrastructural deficiencies of the Railways and lapses in passenger safety, Bihar minister and JD(U) leader Sanjay Kumar Jha said, noting that Nitish Kumar had resigned as railway minister in August 1999 taking moral responsibility for the Gasel train Gurdeep Singh Sappal, co-ordinator in the Congress president's office, said, "Resignation in such cases is expected not just on moral grounds. Resignation is also a means to ensure that those in power and accountability for the accident do not influence such 'high-level enquiry'." "That's why the norm is that the officers in the chain of command are suspended and the minister resigns!" he said.

Congress parliamentary party chairperson Sonia Gandhi said she was most pained and anguished by the terrible train disaster in Odisha.

"I extend my deepest sympathy and condolences to all the bereaved families," she said in a statement.

Kharge and former party chief Rahul Gandhi on Friday night expressed sadness over the tragedy and urged party workers and leaders to extend all support needed for the rescue efforts.

Meanwhile, Congress' media and publicity department head Pawan Khera said the party has decided not to participate in any TV debates this evening on account of the train tragedy in Odisha.

"This is the time to come together and stand by the grieving families. The Congress Party has decided not to participate in any TV debates this evening on account of the ghastly train tragedy in Odisha," Khera said on Twitter.

"Our heartfelt condolences are with the families of those who lost their valuable lives," he said.

President of the ruling Bharatiya Janata Party, JP Nadda, in a tweet said the BJP has decided to postpone all its programmes marking the completion of nine years of its government at the Centre in the wake of the accident.

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