A section of a highway bridge collapsed in the Italian city of Genoa during heavy rain on Tuesday, plummeting vehicles up to 90 metres to the ground and killing at least 22 people, officials said.The vice minister for infrastructure, Edoardo Rixi, said the death toll was expected to rise, while Transport Minister Danilo Toninelli said it was likely to be "an immense tragedy", the BBC reported.The 100-metre (328-feet), two-lane section of the Morandi bridge collapsed in the afternoon. Firefighting crews were searching alongside urban search and rescue teams for people trapped in their vehicles under the rubble.The police linked the disaster to what they called "a violent cloudburst". According to reports, the collapsed section had mostly fallen on to rail tracks below. The bridge stands on the A10 toll motorway, which serves the Italian Riviera and southern coast of France.It was built in the 1960s and the missing section was dozens of metres in length. It ran across the span of the Polcevera stream. Video footage appeared to show one of the towers holding up the suspension bridge collapsing in stormy weather."It was just after 11.30 when we saw lightning strike the bridge," eyewitness Pietro M all'Asa was quoted as saying by Italy's Ansa news agency. "And we saw the bridge going down."Traffic was queuing on the bridge at the time, another eyewitness told Italian public television.One image posted by the regional emergency services showed a truck perched at the end of the surviving bridge section immediately before the drop.French President Emmanuel Macron tweeted a message of sympathy to the people of Italy and said he was ready to offer any necessary aid.Local media estimated that around 10 vehicles could be trapped in the rubble.