New Delhi: The Lok Sabha on Tuesday witnessed ruckus over a sting operation by a news portal allegedly showing Trinamool Congress leaders, including some MPs, accepting bribes in return for favours to a fictitious company. While the Congress, Left and the BJP demanded action in the matter, Trinamool Congress (TMC) leaders rubbished the matter as a "conspiracy" against the ruling party in West Bengal. Communist Party of India-Marxist leader Mohammad Salim, Congress member Adhir Ranjan Choudhury and BJP member S.S. Ahluwalia raised the issue after Question Hour and accused the TMC leaders of hurting the dignity of the lower house by their acts. "We are ashamed that some members of this house were caught red-handed while taking bribe. The matter must be probed and an FIR registered against the accused members. The Lok Sabha had earlier acted against such members, who were even expelled during the 14th Lok Sabha," Salim said. He urged Speaker Sumitra Mahajan to call for the compact discs of the sting operation and act as per the law. Choudhury said: "We all are ashamed of this incident. It's a matter related to the dignity of the house. It should be probed and necessary action taken against those found guilty." Ahluwalia said the matter be referred to the Ethics Committee of the Lok Sabha for necessary action against the culprits. Trinamool Congress leader Saugata Roy hit back. "It is a part of a political conspiracy by the CPI-M, the Congress and the BJP before the West Bengal assembly elections. People who are raising the issue are charged with murder," Roy said. A heated exchange ensued between the Trinamool leaders and Salim. In response, Parliamentary Affairs Minister M. Venkaiah Naidu said truth must prevail in the matter since it was related to the conduct of the members. "The matter needs to be probed either by the government or by the Lok Sabha speaker to establish the truth. Truth must prevail in the case," Naidu said. Poll-bound West Bengal's ruling Trinamool Congress on Monday faced an embarrassing situation after several of its leaders were allegedly caught on camera accepting bribes.