The two BJP leaders were escorted out safely after being locked up for almost four hours.
A BJP minister from Madhya Pradesh found himself locked inside a room by a furious crowd in West Bengal's Singur after the party gave an election ticket to a leader who had just joined from the rival Trinamool Congress.
Biswas Sarange, minister for health and education, and a senior BJP leader from Uttar Pradesh were attending a meeting of the BJP to discuss election strategy in Singur's Apurbapur neighbourhood when a crowd started building up outside the venue.
Soon, the crowd started shouting slogans against the BJP's pick, Rabindranath Bhattacharya, and demanded that the party field "original" BJP candidates instead of Mr Bhattacharya, who recently left Mamata Banerjee's party and joined the BJP.
Many of the protesters were women. Protesters said if the candidate was not changed, they would put up independent candidates and nsure Mr Bhattacharya was defeated.
The two BJP leaders were escorted out safely after being locked up for almost four hours, Hooghly (Rural) police chief Amandeep said.
Mr Bhattacharya, 89, who won from Singur in the last election, left the Trinamool Congress after the party denied him a ticket this time and gave it to Becharam Manna, a former MLA from neighbouring Haripal village. Mr Manna's wife Karabi Manna will contest from Haripal in this election.
Mr Bhattacharya spearheaded the massive protest against Tata Motor's plant in Singur to make the Nano hatchback from 2006 to 2008. Sources have said he wanted the Trinamool Congress to give a ticket to his son and got upset when the party did not.
The CPI(M) has named a young Students' Federation of India leader, Srijan Bhattacharya, to contest from Singur. Mr Bhattacharya has said he will work to bring back manufacturing activity in Singur.
Across Bengal, the rift between leaders who have been with the BJP for a long time and newcomers came out in the open with several party members voicing their disappointment for being denied election tickets.
BJP leader Sovan Chatterjee and party member Baisakhi Bandopadhyay quit the party after both were denied tickets. Mr Chatterjee's constituency for several decades, Behala Purba, was given to Payel Sarkar, who joined the party a few days ago.
As soon as BJP general secretary Arun Singh along with Union Ministers Babul Supriyo and Debasree Chaudhuri released the names of 63 candidates for the third and fourth phases of the election to be held on April 6 and 10, protests broke out in several areas with some leaders openly expressing anger over newcomers being given tickets.
Mr Supriyo and other MPs Locket Chatterjee, Swapan Dasgupta and Nisith Pramanik were enlisted by the BJP to contest the Bengal election.