A jogger has been caught on camera elbowing a female cyclist off her bike as he ran past after she veered slightly into his lane.
The video, which has since racked up thousands of views on social media, shows how the female cyclist tried to overtake other cyclists on a bayside bike lane.
Business manager Michele Dantas, aged 49, filmed the incident as it unfolded in the Brazilian city of Rio de Janeiro on May 22.
The oncoming runner can be seen sticking his elbow out when the woman attempts to overtake another cyclist and her handlebar momentarily straddles the line separating the two lanes.
The footage shows how the runner's apparently intentionally raised elbow hit the cyclist, causing her to fall onto the woman she was trying to overtake. The runner appeared to have ample space to pass.
Ms Dantas who was cycling behind when the incident occurred, said she too lost her balance but managed to avoid a collision.
"The girl was stunned, apologising and saying she had fallen because the man had elbowed her," she told news site G1.
"Before then, we hadn't seen the video and we were just worried about seeing if she was okay.
"When I saw the video, I was disgusted by the gratuitous malice and the fact that it could have resulted in a more serious accident... it could have been worse."
Ms Dantas said the sharing the path with walkers and runners is a contentious issue.
"The coexistence between pedestrians and cyclists on bike lanes is always complicated, but I've never seen an assault like that before," she said.
The identities of the victim and perpetrator are unknown and it is unclear if the incident was reported to the police.
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