Police said in a release Tuesday night that the three were co-operative and it's not believed they were involved in the matter.
They were not charged.
Shortly after the arrests were made about 10 kilometres from the Mic Mac Mall, police said they had not confirmed a valid threat but officers remained at the shopping centre as a precaution.
Police say they are trying to determine the source of the threats, and whether they were legitimate.
The mall says it will be open for business on Wednesday morning.
Shortly after the mall closed police blocked Everette Street in another section of Dartmouth, but they later reopened it to traffic after police said they found nothing of interest in an empty home that became part of their investigation.
The investigation at the Mic Mac Mall comes a little more than two weeks after two people were charged with conspiracy to commit murder at the Halifax Shopping Centre in an alleged Valentine's Day plot that police say could have resulted in mass casualties.
Police say they received information about the potential threat to the Mic Mac Mall at 9 a.m. The mall announced it was closing for the day about 2 1/2 hours after police were made aware of the potential threat.
Halifax Regional School Board placed two of its schools on "hold and secure" because of nearby police operations, but those restrictions were lifted by mid-afternoon.