The man, who was in his 60s, was executed by hanging, along with around 37 other suspected terrorists on Thursday.
The Swedish Foreign Ministry (UD) had protested the death sentence handed to him, and PM Stefan Löfven has now personally taken up the case with Iraq.
“We've had intensive consular activity since we were made aware of this. We protested the death sentence and took it up at a high level with Iraqi representatives,” UD deputy director Patric Nilsson told news agency TT.
The man was sentenced to death in 2010 for terror crimes by an Iraqi court. Iraq’s justice minister Haidar al-Zamali was reportedly at the scene when the prisoners were executed in the city of al-Nasiriyya in the south of the country, according to news agency AFP.
“I have no details, but we knew this person has been in prison in Iraq, accused of terror offences,” PM Stefan Löfven explained.
“Our position is that if you travel to another country and commit crimes, you can expect to be punished in that country. We have however also previously raised our basic opposition to the death penalty.”
UD is aware of further cases of Swedish citizens detained in Iraq, but did not detail whether any have been sentenced to death.
“We've stated that the death sentence should not be carried out, but rather converted to prison sentences. We’ve emphasized the Sweden opposes the death penalty,” UD’s Nilsson noted.
According to the local authority in Iraq, the executed man had links with Isis and al-Qaida. The mass execution was the biggest in Iraq since September, when 42 Sunni Muslims were sentenced for terror related crimes.
Amnesty International has criticised the legal process in Iraq.
“Iraq is one of the five countries in the world that carries out the most executions, and trials in the country do not meet international standards for how a fair trial should go,” Amnesty Sweden spokesperson Ami Hedenborg told TT.
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