An Iraqi asylum seeker was forcibly removed from Australia just as Islamic militants began a brutal campaign which saw four cities in the north and west of the country fall and half a million people displaced.



A removal notice, obtained by Greens immigration spokeswoman, senator Sarah Hanson-Young, and seen by Guardian Australia, shows an Iraqi was returned to Basra, in the south of the country, on 8 June, a day after militants from the radical Sunni group Islamic State in Iraq and Syria (Isis) began advances in the country.



The removal notice shows the Iraqi asylum seeker was flown out of Australia on 7 June under escort. Hanson-Young’s office said the asylum seeker had been heard from in Iraq but his current whereabouts was unknown.



The Australian immigration minister, Scott Morrison, has refused to halt deportations to Iraq since the outbreak of violence despite describing the situation in the country as “very concerning”.



On Wednesday Morrison said that repatriated Iraqi asylum seekers had returned voluntarily.



“We will continue to judge every single case on the merits and on the information available to us,” he told ABC Radio. “ … They themselves are the ones who say they wish to return to their own country and I think it would be a strange situation to detain them when they want to go home.”



The Australian Greens are calling for a moratorium on all returns to Iraq.

• This article was amended on Friday June 20 2014. The original referred to Isis as a Shia group. This has been corrected.



