It was left in the vicinity of a community centre in the Shore Road area.
Tierna Cunningham, the deputy Lord Mayor of Belfast, said young people were taking part in a good relations project upstairs in the building when the alert was telephoned through at around 5.20pm.
The Sinn Féin councillor said the alert had caused "massive disruption."
A residential home, a pub and a number of shops were evacuated along with local houses, Ms Cunningham said.
All residents have since been allowed to return to their homes. The Shore Road was closed between Whitewell Road and the M2 offslip, but re-opened at around 10pm.
Nigel Dodds, North Belfast DUP MP, described the actions of those responsible as "totally and utterly wrong."
"This has caused a great deal of shock within the wider community and I encourage community workers in the area not to be deterred from the positive work they have been engaging in," he said.
"Community Workers from Whitewell, White City, Fairyknowe and Graymount all meet in the surgery alongside young people from each area."
Mr Dodds said that it was clear this occurrence has been an attempt to hinder the partnership work from continuing.