A fire among the rubble held up part of the operation, sending clouds of white smoke up before being extinguished.
A spark from metal-cutting equipment may have caused the blaze in a warehouse under the fallen bridge. Prosecutors say 10 to 20 people might be unaccounted-for and the death toll is expected to rise.
The chance of finding survivors at this stage was slim and the unstable mountains of debris made the search operation unsafe, but rescue workers said they had not given up hope.
The collapse of the Morandi bridge, a decades-old viaduct that crumbled in a storm on Tuesday killing at least 38 people, has stunned and angered the country, with Italian media reporting that some outraged families would shun Saturday's official ceremonies.
The first funerals are being held ahead of a state funeral in Genoa on Saturday to be celebrated by Cardinal Angelo Bagnasco. A trained firefighter, he understood immediately that the structure had collapsed.
Rescuers hope the large chunks of debris may have created a "triangle of survival" when they fell where someone could still be alive, he said.
On Thursday evening the first residents of some buildings in the affected area were allowed to return home, though others are too badly damaged to save.
The collapse has prompted fears over other ageing infrastructure in Italy and overseas, with Bulgaria announcing Thursday a plan to renovate more than 200 bridges while France has said one in three of national road bridges are in need of fix.
Matteo Salvini, deputy prime minister and head of the right-wing League party that governs with the 5-Star Movement, said the procedure for revoking the licence would take "weeks or months".
An engineering study commissioned by toll-highway operator Autostrade per l'Italia a year ago warned about the state of the bridge's concrete-encased cable stays, Italian newspapers reported.
A state of emergency has since been declared, as rescuers continue to look for survivors, while Saturday has been declared a national day of mourning, on which funerals of numerous victims are set to be held. The state funeral will be televised live and broadcaster RAI will not air any advertising, as a sign of respect for the victims.
Shares in Atlantia, parent company of Autostrade, plunged more than 30 percent after the bridge collapse in Genoa on Tuesday, but recovered somewhat on Friday, closing up 5.7 percent.
Atlantia shares were up 6% on Thursday's close by 0900 GMT, still down nearly 22% from their level the day before the disaster.
Meanwhile, Italy's Ministry for Transport said late on Thursday that it would give road operator Autostrade per l'Italia - responsible for maintaining the motorway - 15 days to prove it had taken all necessary steps to ensure the safety of the bridge.