"Ten bodies were found between Sunday afternoon and dawn today. This brings the total number confirmed dead to 34," Dar es Salaam regional commissioner Saidi Mecky Sadicky said on Monday.
"We will continue looking for more bodies and perhaps we will find more," Sadicky said, adding that rescuers managed to excavate the rubble up to the ground floor level but "we will go on until we reach the basement of the building".
Between 60 and 70 people were thought to have been around the partially-built 16-storey building when it came crashing down on Friday morning in the Kisutu area of the coastal city.
At least two children were among those killed and 18 people were rescued alive following the collapse.
Officials said there was little hope of finding any more survivors in the rubble.
Local residents turned out to supply rescuers with food, water and medication.
The ill-fated building is a joint project between the state-owned National Housing Corporation and Ladha Construction Limited.
Sadicky said investigations into the cause of the accident were under way and police held eight people for questioning.
Those arrested were presumed to be the owners of the building and officials from both the construction firm and the Dar es Salaam City Council.
In 2008, another building that collapsed in the economic capital claimed at least four lives. – AFP