Rajya Sabha MP Digvijaya Singh on Sunday hit out at BJP leader Jyotiraditya Scindia, saying that the latter left the Congress even as the party had given him "so much".
Mr Singh said leaving the Congress was not expected from Mr Scindia and his move has dented the credibility in politics.
Mr Singh's criticism of Mr Scindia came on the day the ruling BJP claimed that as many as 35,843 Congress cadres joined the ruling party in the last two days of its three-day membership drive underway in Gwalior.
However, Mr Singh said that the Congress has grown much stronger in the Gwalior-Chambal region after Scindia quit the party.
The BJP's membership drive began in Gwalior on Saturday.
Talking to reporters here on Sunday, state Energy Minister Pradhyuman Singh Tomar said, "As many as 35,843 Congress leaders and workers joined the BJP in two days in the presence of Chief Minister Shivraj Singh Chouhan and RS member Jyotiraditya Scindia."
The minister added that former Congress MP from Morena Barelal Jatav and former Congress MLA from Gwalior rural constituency Ramvaran Gurjar on Sunday joined the BJP.
The Congress, which had held a protest against the BJP's membership drive when it was launched on Saturday, also organised a "dharna" (sit-in) at the Rani Lakshmi Bai memorial on Sunday.
After taking part in the protest, Digvijaya Singh said, "The Congress has given so much to Scindia, still he left the party. It was not expected from him. This has dented the credibility in politics."
"The massive protest of thousands of Congress cadres on Saturday against the BJP's big membership drive on its opening day, speaks of the fact that the party has grown stronger after Mr Scindia's exit," Mr Singh said.
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