The man who went on a shooting rampage in a suburban Dutch mall fired more than 100 rounds in a few minutes as he killed six shoppers before turning one of his weapons on himself, Dutch prosecutors said Monday.
Tristan van der Vlis, 24, used three different guns during the shooting spree Saturday at the busy Ridderhof mall in the central city of Alphen aan den Rijn, prosecutors said in a statement after police had studied video images from mall security cameras.
Dressed in camouflage pants and a black jacket, Van der Vlis shot one man before entering the mall and then walked back and forth firing from three guns as terrified shoppers cowered behind shelves and in the back of stores.
A team of national prosecutors has begun investigating how Van der Vlis could have been granted permits under tough Dutch gun control laws for the three weapons despite prior run-ins with the law and a stay at a psychiatric institution in 2006.
Detectives are still investigating whether one of the guns, a semiautomatic, had been illegally modified to turn it into a fully automatic weapon.
The mall, a small shopping center surrounded by apartment blocks and houses, remained closed Monday. Store owners were expected to be allowed to return late in the afternoon to clear up ahead of reopening Tuesday.
Flowers, meanwhile, continue to pile up at the mall's entrance, left by mourners still trying to come to grips with the apparently motiveless killings.
One message painted in large red letters on a square of cardboard asked simply: "Why? Why?"
Nobody appears to be able to provide an answer.
District attorney Kitty Nook said Sunday that two notes left by the killer and files on his computer gave no clear motive.
"This man was clearly suicidal, and the contents are more of a spiritual than a threatening nature," she told reporters.
Nine people shot by the gunman remained hospitalized Monday, including one in a critical condition, Mayor Bas Eenhoorn said. Van der Vlis wounded at least 17 people, including two children.
The rampage only ended when van der Vlis fatally shot himself in the head near a row of supermarket cash registers.