Home Minister Salahuddin Ahmed said the Awami League, whose activities he described as banned, did not have the capacity to carry out sabotage surrounding 5 August.
He made the remarks while responding to questions from journalists at the Secretariat on 3 August.
Ahmed said there was no reason for public alarm over the discovery of bombs.
He alleged that an unnamed party was trying to undermine communal harmony.
The minister said investigators were examining the discovery of a bag containing bombs in Ashulia.
He said investigators were also checking whether the Ashulia incident was connected to other events.
Ahmed said law-enforcement agencies were active in efforts to curb extremist activity.
He said police had been instructed to ensure that vehicles were not left unattended.
On former police chief Benazir Ahmed, the minister said a conditional bail had been granted and that the government was seeking details of its terms through a law firm.
Ahmed said the law firm had been asked to pursue a court petition to cancel the bail and that diplomatic efforts were under way to bring Benazir Ahmed back.
He said authorities suspected that Benazir Ahmed might hold passports from other countries; no supporting documentation was provided in the statements.
Ahmed also said an investigation was under way into an attack connected to a programme of the National Citizen Party.