ROME - The motorway bridge that collapsed in Genoa, Italy, on Tuesday killed at least 22 people and the death toll will rise, Italian Deputy Transport Minister Edoardo Rixi said in a television interview.

"It's not acceptable that such an important bridge... was not built to avoid this kind of collapse," Rixi said on SkyNews24, speaking from Genoa. "The central section came down."

Italian Transport Minister Danilo Toninelli said on Twitter: "following with great apprehension what seems like an immense tragedy".

The ANSA news agency said authorities believe structural weaknesses may have caused the collapse of the 200 meter section of the Morandi Bridge on the A10 motorway, during a violent storm.