Police recovered at least 30 hand grenades from an abandoned house belonging to an expatriate in the Poragachha area of Char Union in Naria Upazila on Thursday.
According to local and police sources, the property belongs to Milan Madabar, a long-time expatriate residing in Oman.
The house had been unoccupied for an extended period.
Tipped-off, police conducted a raid at the premises on Thursday afternoon and discovered 30 hand grenades stored in five buckets.
Following the recoveries, a bomb disposal unit was called to the scene to secure and examine the explosives.
Dr Ashiq Mahmud, additional superintendent of Police (Naria Circle), said police have been on high alert due to potential threats of sabotage around 15 August.
An investigation is underway to determine who stored the explosives and with what intent, he said.
Law enforcement authorities said that efforts are ongoing to identify and apprehend those involved.