Mamata Banerjee on Thursday accused the BJP-led Centre of executing a "blueprint" through the Border Security Force (BSF) of enabling infiltration from Bangladesh to destabilise Bengal and malign the state government.

She warned district magistrates against letting it happen on their watch, vowing to shoot yet another stern missive to Delhi on the matter soon.

The BJP, in turn, accused her of being delusional and fearing a majoritarian consolidation in Bengal in the wake of atrocities on minorities in Bangladesh.

Mamata, during a major administrative review meeting at Nabanna, said the BSF was allowing infiltration through districts bordering Bangladesh.

"Goons are being sent in. Behind this deeply internal activity (of the BSF), there is a blueprint of the central government," said Mamata.

"Guarding the borders is not in our hands, it's the duty of the BSF. Trinamool Congress does not guard the borders. The district magistrates have to know... this is happening, I have information," the chief minister added.

Mamata asked Bengal DGP Rajeev Kumar to probe where infiltrators were going or staying after entering Bengal.

She also brought up a recent crackdown on a fake passport racket by the state police to allege that porous borders were being misused.

"I will write a strong letter of protest to the Centre. I have flagged these concerns with them repeatedly, in the past," said the Trinamool chief, accusing the Centre of falsely blaming her party for infiltration.

"Why don't you protest?" she asked officials at the meeting. "If someone thinks they will aid terrorism to destabilise the state and blame it on Trinamool Congress... it is not Trinamool's fault, borders are controlled by the BSF."

In north Bengal, six of the eight districts (barring Alipurduar and Kalimpong) share an approximately 1,250-kilometre-long border with Bangladesh.

Three frontiers of the BSF — north Bengal, south Bengal and Guwahati — look after the international border in various districts.

Often, Bangladeshi infiltrators are nabbed by the BSF. Attempts to smuggle cattle, intoxicants, narcotics and other contraband items are often reported from the region.

The chief minister also raised questions on the alleged discontinuation of informing the state on international arrivals, underscoring the fact that granting visas to anyone was the Centre's prerogative.

"In the past, we used to get lists of people coming here via flights, but now it has been stopped. We don't know who are entering Bengal through international arrivals," said Mamata.

"I have said many times that we will follow the Centre's decisions on external affairs, but if these things keep happening, we will protest," the chief minister added.

Since the fall of the Sheikh Hasina government in Bangladesh on August 5, 2024, Bangladeshis, especially their minorities, were seen swarming the unfenced stretches of the borders in some of the districts, seeking refuge in India.

They were, however, sent back by the BSF.

Over the past few months, initiatives have also been taken by the administrations in districts like Jalpaiguri to acquire land in the bordering villages so that it could be handed over to the BSF for fencing.

Underscoring Bengal's historical ties, both cultural and linguistic, with Bangladesh, Mamata spoke of her desire for peace.

"People (from Bangladesh) can come here for treatment. But we must be kept duly informed," Mamata added.

Responding sharply to Mamata's assertions, BJP state unit chief Sukanta Majumdar labelled her claims "baseless" and accused Mamata of trying in vain to shield her party's alleged failures.

"The failed Chief Minister of the state, @MamataOfficial, has reached the ultimate level of delusion!" he wrote in a statement on X.

"Despite not providing land to set up outposts for border surveillance, she used to blame the Border Security Force (@BSF_India) for illegal infiltration. But now, crossing all limits of accusations, she has started blaming her own administration's officials! According to her, the incompetent District Magistrates (DMs) and Superintendents of Police (SPs) under her administration are allowing foreign criminals to infiltrate the border to murder the elected representatives of her party," added the junior member of the Modi cabinet on X.

"Until now, she used to hold the opposition responsible for such incidents. But why this sudden shift in Mamata Banerjee’s narrative? Is she trying to shield the misdeeds of her party's looter, criminal representatives by making such claims?" he wrote.

Additional reporting by Avijit Sinha in Siliguri