Shock and dismay filled the German town of Idar-Oberstein Tuesday (September 21)
Days earlier, a 20 year-old gas station worker was shot dead after an argument about a face mask.
Prosecutors say the cashier had asked a 49-year-old man to comply with the rules and cover up.
The customer, who wanted to buy beer, refused and left the store.
He later returned wearing a mask, but pulled it down when he approached the worker, who again asked him to follow the rules.
The suspect then produced a gun and shot the cashier dead.
The killing on Saturday evening has shocked many Germans.
"He was killed because of a face mask, a face mask the customer did not want to put on. I'm sorry but I have no understanding for this person who felt rejected. I'm also wearing a face mask and I have to endure restrictions. Everyone has to endure restrictions. But the majority of people respect them."
The suspect gave himself up at a police station and, according to prosecutors. He said coronavirus measures were causing him stress.
On Tuesday (September 21) politicians responded to messages circulating on social media from far-right groups who deny the coronavirus which showed sympathy towards the shooter.
Justice Minister Christine Lambrecht said it was disgusting how the killing had been misused to fuel hatred.
She said the state must counter the radicalization of coronavirus deniers who are willing to use violence.