Art thieves stole $163M worth of paintings in Zurich, Switzerland on Sunday. Stolen pieces included paintings by Monet and van Gogh. The theft was conducted by masked robbers during business hours, half an hour before closing time. Increasingly sophisticated museum security measures have thwarted nighttime and insider thefts, making smash-and-grab approaches more appealing to thieves, expert Steven Keller said in a 2004 CSO interview. He noted that increasingly sophisticated security measures are thwarted nighttime or insider thefts in museums.”]