Jalpaiguri/Kolkata: Prime Minister Narendra Modi and West Bengal Chief Minister Mamata Banerjee exchanged a flurry of verbal punches on Friday, as he accused her of trying to save those involved in ponzi scheme scams, alleging that opposition parties were coming together to protect fraudsters, touts and criminals. Banerjee hit back by calling him the "master of corruption".

Launching a scathing attack on Banerjee, the Prime Minister wondered why she was so scared of the probe into the scam, and charged her with inviting leaders from all over the country against whom there are either serious allegations of graft or those who were trying to protect the "corrupt" and said none of the offenders will be spared.

"It has happened for the first time in the history of the nation that a Chief Minister sat in a dharna in support of those who looted thousands of poor people. She is trying to protect the looters and those who ruined the lives of the poor," Modi said while addressing a public rally at Churabhandar in the state's Jalpaiguri district.

Banerjee held a 45-hour sit-in protest in the hub of Kolkata following an ugly face-off between the Central Bureau of Investigation officers and personnel of the Kolkata police, when the federal probe agency had shown up near the residence of the Kolkata Police Commissioner Rajeev kumar to quiz him in the ponzi scheme scam case.

Kumar had headed the Special Investigation Team (SIT) formed by Banerjee to probe the multi-billion-rupee financial scandal before the CBI took over the investigation following a Supreme Court order.

"The people of Bengal want to ask her why she is so scared of the probe into the chit fund scam. Why is she holding dharna for those who are accused of callousness in probing the scandal?" Modi questioned.

"I want to assure all the families who suffered in the Saradha, Narada and Rose Valley scams that the 'chowkidaar' (guard) will not spare anybody -- be it the looters or their protectors, no one will be spared," Modi said.

Refering to the January 19 rally of opposition leaders in Kolkata, Modi said: "These leaders came together to protect the fraudsters, touts and criminals... They can assemble as many people as they want to hold dharnas, and gather as many leaders as possible, the people who looted the poor will be punished".

Upping his ante against the Banerjee government, the Prime Minister said the situation in Bengal is such that infiltrators are welcome, but there is a bar on BJP leaders.

"Obstructing rallies, refusing to allow helicopters to land and attacks on BJP functionarie are signals that the land is slipping from under the Trinamool's feet," Modi said, evoking cheers from thousands of party activists present at the rally ground.

In Kolkata, Banerjee minced no words in returning the fire, as she called Modi "master of corruption and arrogance", and one "used to blaring out a bunch of lies".

"Country has not seen any person as corrupt as Modi. From Rafale to the scheme of 59 minutes loans for MSMEs, to demonetisation, Jan Dhan -- these are all scams. All the institutions have been destroyed.

"He is a master of corruption, arrogance and used to blaring out a bunch of lies. His standard is so below par, we cannot imagine it even. We respect the chair but not Maddy babu," Banerjee said, distorting Modi's name.

Describing the Centre's plan to take action against five senior police officers who were involved in the face-off between the Kolkata Police and CBI officials as part of "campaign" before polls, Banerjee said the Centre cannot take action against them, as they were state officers.

Banerjee also found fault with Modi for inaugurating the circuit bench of the Calcutta High Court in north Bengal's Jalpaiguri, alleging he was "doing politics" by inguarating projects "hurriedly" ahead of the polls.

"I am ashamed to talk about this man. The circuit bench is under the Calcutta High Court. Was anyone from the Calcutta High Court present at the inauguration? Neither state government (officials) nor anyone from high court was present there," Banerjee said.

She alleged that the Central government did not spend a single penny on the circuit bench project in which about Rs 300 crore were spent by the state.