A dump truck has smashed into a pedestrian bridge on a busy highway in northern Rio de Janeiro, causing the walkway to collapse onto three cars and a motorcycle below.
At least four people were killed in the accident, Brazilian authorities said.
Another four people were injured, according to Lamsa, a private company that administers the toll road.
Witnesses said that there were only two people on the yellow metal pedestrian bridge when the accident occurred just after 9am. Normally it would be crowded at that hour, but is in less use because of Brazil's summer holidays.
Mayor Eduardo Paes told reporters at the scene that the trailer of the truck was clearly above the 4.5 metres permitted for use on the highway, known as the Yellow Line road, which cuts through gritty northern and western portions of Rio.
Paes said authorities were trying to confirm if the truck's bed was raised when it hit the walkway. Regardless, "an infraction was being committed because trucks aren't allowed on the Yellow Line at that time of day."
Valeria da Paixao, the director of a daycare centre near the site of the accident, told Globo TV that she "heard a loud noise, like an explosion."
"The walkway is used by many mothers who bring their children to our school," she said. "Thank God it's vacation time and we're closed. If it happened when the school was open we would have had a major tragedy."