The crisis within the Shiv Sena (Uddhav Balasaheb Thackeray) deepened on Thursday, with dissidents citing fears of a possible merger with the Congress as the trigger for their revolt, and Maharashtra authorities extending enhanced security cover to six lawmakers at the centre of the rebellion.Congress merger fears, rebel MPs push Uddhav Sena to brink of split (PTI)The developments mark the third major political split in Maharashtra in four years, following the Shiv Sena and Nationalist Congress Party breakaways in 2022 and 2023, respectively. The latest turmoil comes just days after 20 rebel Trinamool Congress MPs proposed merging with the Nationalist Citizens Party of India and extending support to the BJP-led National Democratic Alliance (NDA), fuelling speculation about fresh political realignments.Also Read | Amid TMC, Shiv Sena (UBT) rebellions, the numbers that could benefit NDA in ParliamentSix MPs skip meetingThe rebellion became more apparent after six of the nine Shiv Sena (UBT) Lok Sabha MPs skipped a parliamentary party meeting in New Delhi on Thursday despite a whip issued by party leadership.The meeting had been convened to assess support for Shiv Sena (UBT) chief Uddhav Thackeray and determine whether a split could be averted. The absence of six MPs was significant because under the anti-defection law, at least two-thirds of a legislature party is required to form a separate group and avoid disqualification.Only three MPs – Arvind Sawant, Anil Desai and Rajabhau Waje – attended the meeting.A day earlier, the rebels had signed a letter seeking recognition as a separate group ahead of a proposed merger with the Shiv Sena led by Maharashtra deputy chief minister Eknath Shinde.UBT Sena-Congress merger fear behind rebellion?A key reason behind the revolt, according to leaders aligned with the Shinde camp, is the belief among several Shiv Sena (UBT) MPs that the party was moving closer to the Congress.Addressing a press conference, Shiv Sena MP Naresh Mhaske claimed that several MPs had repeatedly sought a meeting with Uddhav Thackeray through Arvind Sawant but received no response.According to Mhaske, the MPs feared that the party could eventually be merged with the Congress and decided to chart a separate course. He also alleged that Sanjay Raut had become an "agent of Congress" and accused him of influencing the party's direction.The rebels have also pointed to Raut's reported suggestion that the Trinamool Congress should merge with the Congress, saying it reinforced their fears that a similar move could be attempted within Shiv Sena (UBT). They instead favoured a merger with the Shinde-led Shiv Sena.Raut escalates attack on rebel MPsEven as the rebellion gathered momentum, Sanjay Raut continued his sharp criticism of the dissidents.Soon after Thursday's parliamentary party meeting, the Rajya Sabha MP described the absentee lawmakers as "traitors, dishonest, and frauds" and accused them of betraying the party.The remarks came a day after Shiv Sena spokesperson Sheetal Mhatre criticised Raut's approach, saying the party should have engaged with the disgruntled MPs instead of threatening them."They showed a lack of confidence in the six MPs and are threatening them. They are talking of beating the MPs. Is Sanjay Raut trying to damage the Sena (UBT) by doing all this? The Sena (UBT) should have established a dialogue with the MPs," Mhatre said.Raut, however, warned of legal action against the rebels."You are still party members. You won the election on our party's name and symbol. If you violate the whip, legal action will follow. You can see on TV, people are out on the streets in the constituencies of these people. This time, betrayal will cost Eknath Shinde and these traitors dearly. BJP will also have to pay a price for dirtying politics. Arvind Sawant is preparing the documentation for the disqualification letter," he said.Security cover enhanced for six rebelsAmid the escalating political confrontation, the Maharashtra intelligence department has provided security equivalent to the Y-plus category to six rebel MPs — Sanjay Dina Patil, Nagesh Patil Ashtikar, Om Raje Nimbalkar, Bhausaheb Wakchaure, Sanjay Deshmukh and Sanjay Jadhav.According to an order issued by State Intelligence Commissioner Shirish Jain on June 17, the enhanced security was granted because of possible threats to the lawmakers, a news agency PTI report added.The order authorises local police commanders to increase or reduce security arrangements depending on circumstances and directs police units across Maharashtra to take precautions during the MPs' visits.Reacting to the move, Raut challenged the rebels and the Shinde camp. He said if they had the courage, they should move around without security protection.(With inputs from Yogesh Naik, HT correspondents)