Australian Greens immigration spokesman Nick McKim said he would not give up fighting for the freedom of refugees on Manus Island and Nauru after being deported from Manus Island on Friday.
The Tasmanian senator was deported from Manus Island in Papua New Guinea on the sixth anniversary of the commencement of indefinite offshore detention.
Senator McKim said he was ordered to leave Papua New Guinea despite having a valid passport and multiple entry visa.
On Thursday, Senator McKim was with Iranian journalist and Manus detainee Behrouz Boochani at Lorengau when he was denied entry to the East Lorengau Refugee Transit Centre and had his passport confiscated.
He was later had his passport returned and was told by authorities he would be issued a deportation notice later that day.
"The veil of secrecy continues to surround Australia's detention centres on Manus Island and Nauru," Senator McKim said.
Senator McKim has visited Manus Island six times with the purpose of reporting on the conditions of Australia's offshore detention facilities.
"As a member of the Australian Parliament it is my duty to examine the conditions in which Australia's detainees are being kept," he said.
"This has been six long years of cruelty and deprivation.
"The mental health of detainees is at an all-time low.
"The Australian Greens will continue fighting to ensure all refugees and people seeking asylum on Manus Island and Nauru are given the freedom and safety they so desperately need.
"It is the Labor and Liberal parties who wear the shame of this bloody chapter, not the people of Papua New Guinea."
Refugee advocacy groups around Australia are planning to mark six years of indefinite detention on Manus Island and Nauru with actions held this weekend in Hobart.
The Tassie Nannas, whose protests take the form of knitting in public spaces and talking with people interested as they pass by, will march to the office of Tasmanian Liberal Senator Jonathon Duniam to deliver their message on Friday afternoon.
The Amnesty International Refugee Rights Action Group Tasmania will hold a special honkathon on the corner of Murray and Macquarie Streets from 4.30pm to 6pm on Friday.
GetUp! will also host a rally on Parliament Lawns on Saturday from 2pm.