Both locations were secured and deemed safe overnight on Saturday.
Longford County Council has condemned those responsible for hoax bomb threats over the weekend.
Hundreds of staff and customers were forced to evacuate Dunnes Stores and the Longford Shopping Centre.
Gardaí, emergency services, and members of the Defence Forces responded to two calls.
Both locations were secured and deemed safe overnight on Saturday.
Cathaoirleach of Longford County Council, Colm Murray, is urging anyone with information to contact Gardaí: