NEW CCTV footage has been released showing the moment a motorway bridge collapsed, leaving 43 people dead and four critically injured.

Investigations continue into the disaster after rescue workers found the bodies of three members of a family in the wreckage of Genoa's collapsed motorway bridge on Monday.

The three were the last people reported missing in the disaster and bringing the death toll to 43.

The bodies were recovered from a car crushed under slabs of concrete, the Genoa prefecture said on Sunday, five days after a 200-metre section of the Morandi bridge gave way in busy traffic, plunging vehicles and debris to the ground 50 metres below.

Nine people are still in hospital, four in a critical condition, the prefecture added.

All those listed as missing had now been accounted for, but crews would keep looking just in case, fire brigade official Stefano Zanut told Sky TG24.

"We won't stop. Our work continues in order to have the full certainty that nobody has been left under the rubble," he said.

Workers were also making the site secure and helping investigations to establish the cause of the disaster, he added.

The viaduct was part of the A10 motorway linking the Italian port city with the French border to the west and was managed by toll-road operator Autostrade per l'Italia, a unit of infrastructure group Atlantia.

Autostrade pledged half a billion euros (about $A780,000) on Saturday to rebuild the bridge and set up funds to immediately assist the families of the victims and those displaced from their homes by the collapse and reconstruction work.

The government has also allocated 32 million euros.

"Now we expect things to move fast and that people (who had to leave their homes) are given a place to stay," Prime Minister Conte posted on his Facebook profile.

The head of the regional government, Giovanni Toti, said the first temporary homes would be delivered on Monday and that all those who had to leave their apartments close to the bridge would be accommodated in the next two months. Around 300 houses would be made available, he added.

The government will launch a plan next month aimed at making Italy's infrastructure safe, Giancarlo Giorgetti, undersecretary in the prime minister's office, said in a newspaper interview, saying it would include motorways, bridges and viaducts but also public buildings such as schools.