NDA members staged a walk-out in the Lok Sabha today to register their protest against the ‘‘disregard’’ shown by Railway Minister Laloo Prasad Yadav for the House in the aftermath of the train accident in Punjab.As soon as Laloo finished making his statement, BJP Deputy Leader in the Lok Sabha Vijay Kumar Malhotra said that the Minister, instead of informing the House about the details of the accident, had left for Bihar. ‘‘This is an insult to the House,’’ he said. He added that Laloo had termed the accident a cold-blooded murder even before the inquiry had begun. ‘‘Who is responsible for this murder,’’ he asked. ‘‘The way the Minister behaved, we are going out of the House,’’ he added.Laloo began his statement by expressing regret he was not present in the House yesterday. He said he had informed the Speaker he would reach Delhi at 5 pm and make a statement. When he reached the Capital, he was told the House had been adjourned.