Former West Bengal minister Suvendu Adhikari and MP Sunil Mondal, both of whom recently joined the BJP from the TMC, faced protests allegedly by members of the ruling party in the state near the saffron party's office here on Saturday.
The TMC said the "spontaneous protests" reflected "people's anger against the turncoats".
The back-to-back incidents took place when the two BJP leaders were inside their cars in Hastings area of Kolkata, police said.
The BJP claimed that the protesters banged on Mondal's car and pelted it with stones while he was on his way to the party office.
"Some TMC activists, who were participating in a programme, blocked his (Mondal's) car. They sat on the road to prevent him from going to our office. They also banged on the window panes and pelted his vehicle with stones," BJP's Barrackpore MP Arjun Singh said.
This led to a scuffle between BJP activists and TMC workers, he said.
Police reached the spot and ensured the safe passage of Mondal's car, a senior officer said.
"This shows the true colours of the TMC. They don't believe in any democratic norm. Is this a way to treat a people's representative?" Mondal said.
Adhikari, who during the BJP programme said he was ashamed to have been part of "tyrant" TMC for 21 years, was also subjected to sloganeering by the alleged TMC members while he was leaving the venue.
His car with security cover left the spot as policemen put up barriers separating the road in front of the BJP office from the small dais erected nearby for organising the TMC meeting.
Adhikari was not available for comments.
Along with Adhikari and five TMC MLAs, Mondal, Barddhaman Purba MP, had joined the BJP during Union Home Minister Amit Shah's rally at Midnapore on December 19.
The TMC said the incident was a reflection of people's anger against the turncoats.
"The spontaneous protest was people's anger against the turncoats," TMC MP Saugata Roy said.
BJP sources said party national general secretary Kailash Vijayvargiya informed Shah about the "attack" on Mondal's vehicle.
"The earlier attack on BJP chief J P Nadda's convoy and today's stone-pelting on Mondal's car shows that law and order has collapsed in West Bengal. The TMC is not allowing democratic activities of its political opponents," party state chief Dilip Ghosh said.
