A pro-Isis group yesterday urged supporters of the jihadists to attack targets such as markets and hospitals in Europe over the holiday and urged Muslims to stay away from Christian celebrations.
The threat came as European authorities have stepped up security following an attack claimed by Isis (Islamic State) in which a truck ploughed into crowds in a Berlin Christmas market and killed 12 people this month.
The Nashir Media Foundation, which backs Isis, posted its message online, accompanied by images of fighters with guns and knives, Santa Claus, reindeer and a Christmas tree, according to the United States-based Site Intelligence Group, which monitors militant groups online.
"Their celebrations, gatherings, clubs, markets, theatres, cinemas, malls and even their hospitals are all perfect targets for you," the online message to Islamist "lone wolves" in Europe said.
It said Isis would "replace their fireworks with explosive belts and devices, and turn their singing and clapping into weeping and wailing".