A European Council watchdog committee on Thursday accused German police of mistreating an Afghan man who was being expelled by choking him and squeezing his genitals.
"To ill-treat a person by squeezing the genitals, a technique which is clearly aimed at inflicting severe pain to gain compliance, is both excessive and inappropriate," the council's Committee for the Prevention of Torture (CPT) said in a report.
It focused on an August 14, 2018 charter flight that carried 46 Afghans from Munich to Kabul on behalf of the EU border agency Frontex after their asylum requests had been denied.
Three CPT representatives were also on the flight, along with about 100 German police officers, six of whom had restrained the Afghan in question.
The mass expulsion took place for the most part in a professional manner, the report said, but one unruly Afghan man was subdued using two controversial techniques, the second being the use of an arm around his neck to temporarily cut off his air supply.
"The CPT considers that any use of force must avoid inducing a sensation of asphyxia on the person concerned,"the report said.
"The CPT recommends that the German authorities take immediate action to end the application of these two techniques by Federal Police escort officers."
In 2016, Germany and Afghanistan signed an accord concerning the expulsion of Afghans whose asylum requests have been rejected, and the CPT is charged with ensuring that the process is not accompanied by acts of torture, or inhuman or degrading treatment.
The expulsions are controversial in Germany owing to the levels of violence and unrest in Afghanistan.