Families alleged all six were injured during attack by TMC workers.
Six BJP activists were injured, two of them critically, in a bomb explosion in West Bengal's South 24 Parganas district, police said on Saturday.
Family members of the injured have alleged that a few members of the local Trinamool Congress hurled bombs at them while they were returning home in Gosaba area of the district from a marriage ceremony late Friday night.
Police, however, claimed that the accident happened inside the house of a BJP activist where the crude bombs which were being manufactured went off accidently.
"We have listened to the claims of the family members of those injured but it seems that they were manufacturing bombs when it exploded," police said.
"We are investigating the matter and talking to the locals," the officer said when contacted over the phone.
Unconfirmed reports said that on Friday night, Gosaba witnessed clashes between TMC-BJP activists when bombs were hurled at each other, leaving six injured.
Nobody has been arrested in connection with the blast, the police officer added.
The injured are undergoing treatment at Canning Sub-Divisional Hospital, he said.
A huge number of policemen have been deployed there as sleuths of the bomb squad and forensic department reached the spot, the officer said.
Gosaba reserved assembly is scheduled to vote in the second phase of the assembly elections on April 1.