MILAN, Italy (CBS News/AP) – A raised highway partially collapsed in the northern Italian port city of Genoa on Tuesday, leaving an unknown number of people trapped under rubble. There was no immediate confirmation of deaths or injuries, but Italian media said that rescuers were digging through the rubble, looking for people in cars that fell.

News agencies reported multiple deaths, and Interior Ministry officials stated that at least 11 people were killed. Transport Minister Danilo Toninelli called the collapse “an immense tragedy,” but he did not immediately confirm any casualties.

At least two people were pulled from the rubble alive. Their conditions were not known.

Authorities suspect that a structural weakness caused the collapse. Italian media stated that the collapsed highway portion was about 200 yards long. Images tweeted by police in Italy showed the highway with a large section missing. French news agency AFP said that it was a portion of the five-decade old Morandi highway bridge that had collapsed.

CBS News reported that maintenance work was being performed on the bridge. Italian fire services said that the bridge, in an industrial area in west Genoa, fell down at 5:00 a.m. Eastern time. Italian officials have also said that the region was hit by a sudden, violent storm just before the collapse.

A fire service spokesperson told AFP that the bridge collapsed primarily onto railroad tracks, about 100 yards below, and that “cars and trucks” had fallen with the rubble. Witnesses said that they believed at least 10 vehicles were trapped under the rubble.

Another video tweeted by Italian police showed part of the actual collapse in what appeared to be cell phone video.

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