Prosecutors in Sicily, acting with Britain’s National Crime Agency (NCA), announced the capture of the notorious Eritrean human trafficker Medhanie Yehdego Mered, 35, in Khartoum in June 2016, hailing it as “the arrest of the year”.

But within hours close friends said the detained man was in fact Medhanie Tesfamariam Berhe, a 29-year-old refugee and former dairy worker. Further evidence from Berhe’s family, Facebook account and even Mered’s wife, Lidya Tesfu, has since confirmed the view that Italian prosecutors have the wrong man.

Berhe’s defence lawyer, Michele Calantropo, flew last month to Sweden, where Tesfu lives with her son – who is listed in the Swedish population registry as Raei Yehdego Mered, and is believed by authorities to be Mered’s first child.

“We took a sample of saliva from the trafficker’s wife and son and crossed it with that of the detained man,” Calantropo said. “The result leaves no room for doubt: the man in prison is not the father of the child, and consequently is not the trafficker Mered.”

The DNA evidence reinforces the results of an earlier test on Berhe’s mother, Meaza Zerai Weldai, 59, who travelled to Palermo from the Eritrean capital, Asmara, last October. Analysis showed she was the mother of the detained man.

It was also reported last year that Mered had been in jail in the United Arab Emirates, on charges of using a forged passport, at the time Italian prosecutors travelled to Sudan to arrest the suspect they believed was the people-smuggler.

A recent documentary by the Swedish public broadcaster SVT in collaboration with Guardian reporters revealed the trafficker known as “the General” is currently living in Uganda, spending his substantial earnings in nightclubs.

Despite now overwhelming evidence to the contrary, Italian prosecutors continue to insist the man captured in Khartoum is the real smuggler – despite not being able to find a single witness to testify against him.

The NCA said it could not comment on a continuing case. Italian prosecutors also declined to comment.