Senior TMC leader Abhishek Banerjee on Tuesday condoled the deaths in the Delhi blast and attacked the Ministry of Home Affairs over what he termed as "grave lapses" in internal security.

At least 12 people were killed after a powerful explosion ripped through a slow-moving car at a traffic signal near the Red Fort metro station on Monday evening.

Banerjee, the TMC national general secretary, said in a post on X that he was "deeply shocked and anguished".

"My heartfelt condolences go out to the bereaved families and my prayers are with those recovering from their injuries. It is extremely distressing that such an incident has taken place in the heart of our national capital," he said.

Attacking the Centre, the Lok Sabha MP said that Delhi Police, which operates under the Union Home Ministry, "bears the primary responsibility for maintaining law and order".

"How, then, are such grave lapses in security being allowed to occur?" he asked.

Banerjee also referred to the seizure of nearly 350 kg of explosives and an assault rifle from Faridabad in Haryana on Sunday, noting that the two incidents, when viewed together, "raise alarming questions about internal security and the evident decline in vigilance".

He demanded an impartial, time-bound investigation.

"An impartial, time-bound investigation must be conducted by a Special Investigation Team (SIT), under court supervision if necessary, to uncover the truth and ensure that those responsible are held fully accountable," he said.

TMC MP Mahua Moitra also attacked Shah over the Delhi blast. The Krishnanagar MP has frequently targeted the BJP leadership over issues of law and order, federalism, and what she describes as the Centre's use of agencies against opposition leaders.

In a post on X, Moitra wrote, "India needs a capable Home Minister not a full-time Hate Campaign Minister. Isn't it @AmitShah's duty to protect both our borders as well as our cities? Why is he failing so spectacularly on all counts?" Her comments came a day after a high-intensity blast near the Red Fort in Delhi left several people dead and many injured, triggering questions over policing and intelligence gaps.

Delhi Police said that the car, in which the blast took place, had three occupants, adding that they are also probing if it was a suicide bomber attack.