Former Trinamool Congress MLA Saokat Molla was arrested by the National Investigation Agency (NIA) in connection with a blast at Bhangar near Kolkata in March.
The blast killed one person and the NIA searched at least eight locations, including Molla's residence and hideouts, in South 24 Parganas and North 24 Parganas.
Molla, a prime suspect and conspirator, was held from South 24 Parganas and will be produced in court on Saturday.
This comes a day after the NIA arrested one accused, Sainur Molla, who transported victims in his SUV after the blast.
Four persons, including Saokat Molla, have been arrested in the case till date.
