Shopkeepers believe that a heavily armed bandit disguised as St Nick has robbed several shops in southern Germany, while another Santa tried to sexually molest an employee at an electronics company near Erfurt.
Newspapers have published numerous accounts - and photographs for those who are not quite sure what Santa looks like - of the robberies, but authorities complain that the thieves often escape because they can quickly blend into the holiday decorations and disappear after their hold-ups.
"A man in a Santa outfit with a long white beard stood politely in line and when he got to the cashier, pulled out a Kalashnikov rifle and started shooting," said Edmund Hart, whose convenience store in Aschaffenburge was robbed. "My clerks were too shocked to do anything but hand him the money," said Mr Hart, who rushed to his shop from a Christmas party to find shattered displays and 18 bullet holes in the wall. "He spoke perfect German without any trace of a dialect, demanded the money and started to shoot."
Mr Hart said customers fled from the shop and the bandit escaped without trace. The shop assistants are being treated for injuries to their ears.
Police believe the same Father Christmas was responsible for a similar attack two days later at a supermarket near Nuremberg where the thief made off with 5,000 marks (pounds 1,740). They have two theories for the Santa Claus crime wave; some amateur crooks find it hard to raise enough money for presents, others take advantage of the holidays as useful cover for the burglaries.
Werner Veith, a spokesman for the Munich police department, said: "Someone running down the street at this time of year in a Santa outfit isn't going to cause much suspicion."
He said that a Father Christmas had stolen more than 100,000 marks from a department store several years ago but was never caught. "With the Santa mask, he just blended right in. We have these sorts of robberies during the Christmas season and during the winter carnival season when many people are on the streets wearing streets and masks and costumes."
But Christmas is not just a time for giving, some unfortunate Santas have been on the receiving end as well.
One Father Christmas who was handing out chocolates in the northern town of Oldenburg was approached by a man who also wanted some. At first the Santa refused but, after arguing reluctantly that it was meant for the children, he gave him a piece. "The man then expressed his gratitude by punching the Santa in the face so hard that he had to be taken to hospital," according to a subsequent newspaper report.