An explosion outside a shuttered sweet-shop godown ripped apart an eight-year-old boy’s legs as he accompanied his mother in Dum Dum’s bustling Nagerbazar on Tuesday morning.

The boy, identified as Bibhas Ghosh, died in a hospital after screaming “O maa go” in pain for most of the way. He would have turned nine on Friday. His mother Sita, 42, is critical.

At least eight others are in hospital, including fruit-seller Ajit Halder, 45, who was barely a foot away from the bomb.

The bomb went off around 9am in front of a five-storeyed building that houses the office of South Dum Dum municipality chairman Panchu Ray who identified himself as the possible target.

Ray, who usually visits the office around 10am every Tuesday to meet local people, said: “It was targeted at me.”

Local MLA and Trinamul Congress leader Purnendu Bose blamed the Rashtriya Swayamsevak Sangh (RSS).

RSS state secretary Jishnu Basu called the allegation “meaningless” talk. “They speak rubbish when they are scared. There should be a probe by the NIA (National Investigation Agency),” he said.

Sources familiar with the area hinted at infighting over real estate spoils.

Some echoed Ray, saying the explosion was probably aimed at sending a message to the chairman to “be more flexible”. Ray had reportedly come in the way of several satraps who would have their hands in almost all real estate projects in the area.

“Jyotipriya (Mullick) had asked me to take police cover,” Ray said, referring to the Bengal food and supplies minister who is also president of Trinamul’s North 24-Parganas unit. “I refused. There is no point fighting for the chair of the chairman. Mamata Banerjee has chosen me.”

Ray, who is in his early 70s, was chief minister Mamata Banerjee’s pick for the post of chairman of the municipality after two groups in the area had started pushing their candidates.

“Whoever placed the bomb was clearly aware of Panchuda’s weekly dates,” said a party worker.

Rajesh Kumar Singh, commissioner of Barrackpore police commissionerate, said a “socket bomb” (in which a can is used to pack explosives) was found outside the godown. (Socket bombs, allegedly sourced from India and China, were said to have been used by the Maoists in the civil war in Nepal.)

Although MLA Bose claimed a timer-fitted device had been used, officer Singh ruled out the possibility of “timers” setting off the bomb but did not specify how it was detonated.

“This was a low-intensity blast. We have collected remnants of the materials that were used to make the bomb. It is still not clear how the bomb found its way to this particular spot,” Singh said. “So far, it appears only one bomb had gone off. The splinters hit the top of the iron shutter and hit other buildings. It is not clear what triggered the explosion. Probably pressure.”

The explosion tore through the iron shutter and left a small depression on the concrete on the ground. Residents recalled a “deafening noise and thick dark fumes”.

A homemaker who lives across the road said she rushed to her window and saw four persons writhing in pain. “The child was screaming ‘O maa go’ and it will ring in my ears all my life,” said Tinku Sengupta.

Apples, papayas and sweet lemons lay strewn across the road. Residents said the spot is usually crowded in the mornings when people turn up to buy fruits and sweets. But as Tuesday was a holiday, probably many lives were saved.