It’s been called the “world’s most expensive car crash.” Auto fans across the world are demanding answers to what caused a pile-up on stretch of Japanese highway that laid waste to a small fortune of luxury automobiles — maybe $4 million worth.

A Japanese newscast showed the aftermath of the wreck that claimed 14 vehicles in all, including 8 ferraris, 3 Mercedes, a Lamborghini, a Skyline, and a Prius.

Jalopnik reports that a group of foreign car enthusiasts were heading to Hiroshima from Kyushu when one of the drivers lost control trying to overtake a car on a wet, curved part of China Road in Yamaguchi Prefecture. The Ferrari driver reportedly hit the median and created a reaction that caused the other cars in the lineup to crash.

According to the Telegraph, the massive crash took place Sunday on the Chugoku Expressway, in southwest Japan. No one suffered serious injuries, and the accident shut down the road for six hours as cleanup crews tried to untangle the mess.