An Australian policeman has been placed on "restricted duties" after being filmed tripping up an Aboriginal boy, who was then pinned to the ground.
The video shows the New South Wales Police officer and two colleagues holding the boy down.
The incident ended in the boy's arrest and subsequent release, authorities said. He was taken to hospital briefly for observation.
NSW Police said its professional standards unit would investigate.
The incident happened in the Sydney suburb of Surry Hills on Monday and came to public attention after it was shared on Facebook.
Australian media reported the boy was 16 or 17.
Criticism of police treatment of indigenous Australians has ramped up this week on the back of protests about George Floyd's death in the US. Protests have been planned around Australia.
'You slammed him on the face'
In the video, three officers are seen speaking to a group of teenagers on a brick path.
After the teenager who was later arrested says "I'll crack you in the… jaw, bro" to one officer, the boy is told to "turn around".
The officer then kicks the teenager's legs out from beneath him, causing him to fall to the ground. An onlooker is heard is saying that the boy landed on his face.
The three officers then pin the boy to the ground, arresting him.
NSW Police said the boy was released to his family after being observed for a time in hospital.
"An investigation into the circumstances surrounding the arrest is now under way by officers attached to the Professional Standards Command," a police statement said.
"The constable involved has been placed on restricted duties while this review is carried out.
"Senior officers have met with the community and local elders and will keep them appraised throughout the process."
Indigenous Australians comprise almost 30% of adult prison inmates, despite making up only about 3% of the population, according to the Australian Bureau of Statistics.