Tollygunge (West Bengal), Apr 10 (ANI): Polling began on April 10 for the fourth phase of West Bengal Assembly elections. BJP candidate from Kolkata's Tollygunge, Babul Supriyo arrived at Gandhi Colony Bharati Balika Vidyalaya polling booth, where party's polling agent wasn't being given entry on April 10. “He has ID but wasn't being allowed by Presiding Officer. We showed his details from website. He's allowed now. The biggest challenge is to remove Mamata didi and TMC from West Bengal. Aroop Biswas (TMC candidate from the constituency) has been the right hand of all her works. So is a challenge to change the atmosphere of terror here,” said Supriyo to ANI. Meanwhile, state polls are underway in 44 constituencies.