At least 20 people are dead after a highway bridge collapsed during a violent storm in Italy’s northern city of Genoa on Tuesday.
It’s still unknown exactly what caused the bridge, which was built in the 1960s and is over a kilometre long, to collapse, but authorities are investigating.
The design of the bridge has been criticized in the past. Antonio Brencich, a professor specializing in reinforced concrete construction at the University of Genoa, called the span “a failure of engineering” in an interview in 2016.
“That bridge is wrong. Sooner or later it will have to be replaced. I do not know when. But there will be a time when the cost of maintenance will be higher than a replacement,” he told Italian media Primocanale.
The tragedy also comes a day after a boardwalk in Spain collapsed at a music festival, injuring more than 300 people.
WATCH: Aerials show extent of collapsed bridge in Italy city
There have been a number of deadly bridge collapses over the past few years, including in Canada. On Sept. 20, 2006, the de la Concorde overpass collapsed in Laval, Que., killing five people and injuring six others. A lack of proper inspection, the deterioration of concrete and cracks in the bridge caused the collapse, an investigation found.
Although fatal bridge collapses are rare in Canada, they do happen across the world, mainly due to structural deficiencies and aging infrastructure. Here’s a look at some of the deadliest incidents over the past decade.
Six people were killed and 10 others injured after a pedestrian bridge fell onto a busy eight-lane road in Florida on March 15.
The Florida International University pedestrian bridge was built to connect the campus to student housing in a nearby neighbourhood and was intended to improve pedestrian safety.
Although the exact cause of the collapse is still being investigated, the National Transportation Safety Board said that crews were applying what’s known as “post-tensioning force” on the bridge before the failure. Authorities are investigating whether cracking that was reported just before the span fell contributed to the accident.
WATCH: Time-lapse shows original installation of collapsed Florida bridge
Two people were killed and two others were injured after an overpass collapsed on top of a highway in central Italy on March 9, 2017.
The Italian highway company Autostrade per l’Italia said that the bridge was a temporary structure to support an overpass that had been closed to traffic.
The bridge was undergoing maintenance work at the time, and the collapse happened after the sudden failure of the structure supporting the overpass, local authorities said.
WATCH: Couple killed after highway overpass collapses onto major Italian throughway
On Oct. 28, 2016, a bridge collapsed over a busy road in northern Italy, killing one person and injuring five others.
The incident was blamed on bureaucratic bungling which led to a fatal delay in the bridge’s closure after it was reported to have significant cracks. The bridge fell under the weight of a tractor-trailer that had special permission to carry an exceptionally heavy load but should have been diverted to a different road.
In the middle of the night on Aug. 2, 2016, a road bridge collapsed in west-central India, sending vehicles and buses into the fast-flowing Siviti river. Twenty-eight people were killed.
The cause of the collapse was due to the bridge’s dilapidated condition. The bridge was around 100 years old.
On March 31, 2016, an overpass under construction in Kolkata, India collapsed, killing 26 people and injuring dozens more.
The overpass was under construction and the day before the collapse, concrete was laid on it.
An internal investigation into the collapse revealed that the design of the overpass was faulty. The report also claimed a lack of quality control, inconsistency in construction material and faulty approval of the design caused the collapse.
In April 2016, local police charged the company contracted to build the structure with attempted murder and criminal conspiracy.
WATCH: Overpass buckles in Kolkata, trapping people
On July 2, 2014, an overpass collapsed in Belo Horizonte, Brazil, killing two people and injuring 22 others.
The bridge, which was under construction at the time, collapsed as vehicles were passing on a busy road underneath.
The construction project was part of infrastructural improvements meant to prepare for the 2014 FIFA World Cup that was taking place at the time of the collapse.
WATCH: Protesters blame Brazil government for bridge collapse
On Aug. 24, 2012, one of the longest bridges in northern China collapsed, just nine months after it opened.
The ramp on the Yangmingtan Bridge in the city of Harbin dropped to the ground and four trucks plummeted with it, resulting in three deaths and five injuries.
Chinese officials blamed overloaded trucks for the collapse. But there were also questions surrounding materials used during the construction and whether the projects were properly engineered, according to the New York Times.
The suspension bridge located on the island of Borneo, Indonesia, collapsed on Nov. 26, 2011, causing a bus, cars and motorcycles to plunge into the river. Twenty people were killed and 40 others injured.
The bridge collapsed while workers were performing maintenance on the bridge and a support cable snapped.
On Dec. 24, 2009, 48 workers were killed after an under-construction bridge collapsed in the Chambal river in India.
An investigation into the collapse identified non-compliance of the construction sequence by the project designer as one of the main reasons behind the accident.
© 2018 Global News, a division of Corus Entertainment Inc.