People are dying from extreme heat, which is also killing a large number of chickens and destroying tea plants
Police said the incident occurred around 9pm on Monday at the Upazila's Jinjira Bazar.
The shop's owner Gobinda Chanrda Barman told bdnews24.com that 10 to 12 men barged into his shop after exploding crude bombs in the area.
Armed with pistols and sharp weapons, they held the staff at hostage and made off with ornaments, cash and even the security cameras, he said. "They left on five motorcycles hurling crude bombs."
Keraniganj Police OC Ferdous Hossain said they have launched an investigation.