Brazilian authorities say a baby was killed and 17 people were injured when a motorist drove into a crowded boardwalk along Copacabana beach.
Two children and an Australian tourist were among those injured.
Eight other people remain in hospital, many with broken bones.
A baby has died and at least 15 people have been injured after a auto ploughed into a crowd at Rio's Copacabana beach.
Brazilian military police said there was no indication that the incident was a terrorist attack. Military police said on Twitter that at least 11 people were injured and that the driver has been taken into custody.
The driver is suspected to have suffered some kind of epileptic attack, according to the Civil Police of Rio de Janeiro State.
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Police have arrested the driver, who told them he had not been drinking but had lost control of his vehicle.
Military police are also participating, though authorities have not said how many.
The report said 437 Brazilian police officers were slain in 2016, a lot of them while off duty.
The promenade was busy at the time of the accident with people enjoying the warm summer evening.
The vehicle stopped in the sand after it apparently crossed the wide sidewalk that runs between the beach and a busy road.