Two construction labourers were injured when crude bombs went off at an under-construction building site of a Trinamul’s gram panchayat member in Deganga, North 24-Parganas, on Sunday morning.

Police and local sources said that at least two bombs exploded when the masons were cleaning a part of the floor with a spade under a staircase at the new residential building of Berachampa-II panchayat member Sahi Sultana located in the Uttar Chandpur village.

Residents heard a deafening sound and rushed to Sultana’s house, where they found two labourers lying unconscious in a pool of blood. They immediately called police, who took them to a hospital in Deganga.

Police later recovered three crude bombs from the blast site.

Panchayat member Sahi Sultana claimed ignorance about the source of the bombs.

“I suffered a jolt due to the blast.... I don’t know how the bombs came there,” she said.

Abdul Hakim Mollah, a Trinamul leader, and husband of the panchayat member, alleged a “conspiracy” behind the blast. “It is an under-construction house with no protection. It appears that the bombs were planted to malign my wife and me. We are deeply shocked. We told the police to find out the culprits who planted the bombs.”

Both the masons suffered injuries on their faces and legs, police said.

The incident embarrassed the local Trinamul leadership, which refused to comment saying the matter is being “looked into by police”. Trinamul leader and North 24-Parganas zilla parishad member A.K.M Farhad told The Telegraph, “We have told police to unlid the mystery and to nab the culprits.”

A section of Trinamul leaders indicated that bombs were stacked to settle scores with a rival faction. Local sources said owing to rivalry between two groups of the ruling party, the area had been tense during the past few days.

On Saturday, two erring groups clashed at a mango orchard near to a Duare Sarkar camp, when at least four bombs were hurled.

Deganga police have begun a probe. However, the sleuths could not arrest anybody in connection with the incident.

In a separate incident, a bomb exploded on a running motorcycle near the Matia area of Basirhat on Sunday morning. Police said the motorcyclist, who was injured in the incident was carrying the bombs when it went off.