Police were called to Felix Street after midday Thursday in response to two “suspicious” vehicles that racked up parking tickets for several days outside Waterfront Place.
The building houses a number of Commonwealth offices and Immigration Minister Peter Dutton also held a media conference not long before Felix Street was closed.
Workers from other nearby buildings were barred from entering as bomb squad officers inspected underneath the cars, including an older-model Toyota Camry, using mirrors.
Firefighters and an ambulance crew attended and remained on stand-by as the lower part of Mary Street was also cordoned off and closed for several hours.
Police later gained access to the Camry and searched its interior before its owner – a man in his 20s wearing a blue t-shirt and jeans – arrived to claim it.
The second vehicle was also claimed and the two streets reopened at 5pm.
Inspector Glenn Morris said specialist police attended due to the potential risk to public safety.
“We erred on the side of caution,” he said.
“Public safety is our primary concern.”
The vehicles’ owners would not be facing any charges, he said.
“We have no concerns in relation to either them or the vehicles.”