Officials said more people than initially thought were still trapped in the wreckage of the department store, which collapsed due to suspected structural failure, but they declined to provide an estimate.
"The first 48 hours are very critical and it is my hope that we'd be able to reach anybody trapped down there as soon as possible," Ghanaian President John Dramani Mahama said at a news conference near the collapsed building.
Accra is in the midst of a construction boom spurred by oil-fuelled economic growth, but building standards region-wide are generally poor and enforcement is often lax.
Ghana authorities initially had estimated that around 55 people were inside the building when it collapsed on Wednesday morning, but that figure was based on the number of employees and did not factor in the number of shoppers too.
By Thursday afternoon, emergency personnel had pulled out 69 survivors and recovered nine bodies from the building, which housed a mall operated by Indian retailer Melcom Ltd.
"It is now clear that more people were in the shop than initially estimated, and it is difficult to tell the actual numbers at this moment," Kofi Portuphy, the head of Ghana's National Disaster Management Organisation, told Reuters.
He said a team from the Israeli Defence Forces had arrived and was using trained sniffer dogs, concrete cutters and other equipment to locate any remaining survivors.
"Certainly the conditions of any survivors down there will be deteriorating and it is our hope to get them out as quickly as we can," Portuphy said.
The ambulance service shuttling victims from the site to a local hospital said survivors had sustained injuries of varying degrees of seriousness.
President Mahama promised an inquiry into how the building's owner was able to circumvent building codes, after it was discovered that its construction had not been approved by city authorities.
"Drastic action will be taken and the city authorities are going to be held responsible," he said. "Anyone found culpable will face the full rigours of the law."
Investigators questioned an Accra building inspection director and a Melcom official on Thursday and were still seeking the building's owner, deputy Information Minister Samuel Okudzeto Ablakwa told Reuters.
Running for election in December, Mahama cut short a campaign tour to visit the site.
Melcom runs Ghana's biggest chain of retail department stores and has some 20 shops nationwide. It said it rented the collapsed building and had opened a store there in January.
It said it was closing all its shops in the capital on Thursday as a mark of respect for the loss of lives.