Slovakia's prime minister has drawn criticism from across Europe and from his own people after his surprise visit to Moscow for face-to-face talks with Vladimir Putin on Sunday.
The suspect in the German Christmas market attack "threatened to do something that would attract international attention" in 2013 and was flagged as a potential threat the following year, according to a state interior minister.
The Albanian government plans to block access to TikTok for a year after the killing of a 14-year-old boy led to concerns about social media's influence on children.
A memorial service has taken place in Magdeburg, Germany, for the victims of a Christmas market attack - as police said four women were among those killed in Friday night's attack.
The suspect in the attack on the Christmas market in Magdeburg appeared to be dissatisfied with the treatment of Saudi refugees in Germany, a prosecutor has said.