A man in Brazil was knocked out cold by a flying tyre that seemed to appear out of nowhere, reports said.
The freak accident was captured on a closed-circuit television camera.
Mr Roberto Carlos Fernandes, 50, was walking with his wife in Ipatinga, Brazil, when the tyre hit him square on the back of his head.
His face was planted into the road as his wife looked on in shock. Passers-by stopped to help.
The rogue wheel had bounced quite a distance from a road behind them.
The date stamp on the video, which has gone viral around the world, is Feb 17.
Mr Fernandes was in intensive care with a fractured skull and injuries to his chest, but his condition has stabilised,according to news reports.
Police said they could not identify which car the tyre came from, according to The Daily Mail.