A man suspected of shooting a petrol station cashier dead in Germany has been connected with coronavirus conspiracy groups and the far right.

       The 49-year-old man was arrested on Sunday, a day after a 20-year-old clerk was shot in the head with a revolver in Idar-Oberstein, a town in the west of the country.

       Researchers found he had openly supported the far-right Alternative for Germany (AfD) party on social media. They also believe he is a coronavirus denier.

       Earlier this week, the German health minister Jens Spahn told reporters the suspect had been asked to wear a mask - a requirement for shoppers in Germany - by the cashier, who has not yet been named.

       After first heading home, the man then returned to the shop, where he is alleged to have killed the victim.

       Mr Spahn said that “incitement” posted on social media created the atmosphere in which such a crime could occur.

       He also blamed the chant of “Traitors!” by coronavirus sceptics at anti-lockdown demonstrations during the pandemic for legitimizing violence.

       "We must clearly and decisively say ‘no’ to any form of pandemic extremism," he said.

       In a similar vein, Stephan Kramer, who runs the intelligence services in the state of Thuringia, told the RND network there had been a pronounced increase in aggressive actions recently.

       "The escalation of right-wing conspiracy fantasies among aggressive and violence-prone citizens has been obvious for months," he said.

       The leaders of Germany’s main political parties condemned the shooting, with Annalena Baerbock, of the Green party, saying she was “shaken by this terrible murder of a young man who merely asked that existing rules be followed”.

       The Christian Democratic Union’s Armin Laschet called it a “horrible” crime, while Olaf Scholz, the leader of the Social Democrats (SPD), said the country should “resolutely stand up to hatred”.

       Additional reporting by agencies