The perpetrator of the deadly truck attack on the Christmas market in Berlin may have acquired the gun he used to hijack a vehicle in Switzerland, German media reported.
According to the ZDF broadcaster, Tunisian migrant Anis Amri, could have received the gun from a person named Erma during one of his visits to Switzerland.
The Swiss prosecution confirmed that an investigation concerning this information and potential Amri's contacts in the country was launched.
The broadcaster added that in July 2016 Amri had been detained by the German police near the border with Switzerland.
Amri reportedly had drugs and two Italian passports on him and was heading to a wedding in the Swiss city of Zurich.
The 24-year-old Tunisian, who had his application for asylum rejected in June last year, rammed a stolen truck into a busy Christmas market in central Berlin in on December 19, killing 12 people.
Amri fled to Italy where he was shot dead by Milan police officers several days after the attack. It emerged later that he had pledged allegiance to the terrorist ISIL group.