Protesters clashed with police in Brisbane last night as they sought unsuccessfully to stop an asylum seeker from being flown back to Nauru.
The Afghan asylum seeker had been sent to Brisbane around two weeks ago after suffering deep vein thrombosis or DVT.
Police say protesters blocked a car driven by immigration authorities with the Afghan man inside.
A police spokesperson says two police received minor injuries in the incident.
A protester also suffered a minor leg injury when, according to police he tried to put his leg under the wheels of the car.
The Afghan man had been brought to Australia in the last two weeks to receive medical treatment for DVT.
A Greens spokesperson, Amanda Curr, says the man was unfit to travel.
She says she believes doctors had been pressured by Department of Immigration officials into releasing the asylum seeker.
A spokeswoman for the Department of Immigration says no-one is returned to a detention centre until medically fit to travel and says no doctors had been put under pressure to release the man.