Police in Amsterdam are investigating whether criminals caused an explosion at an apartment building that injured seven people and forced 400 residents to evacuate.
Three people have been detained, police said on Saturday. After an extensive rescue operation, officials now believe there are no more victims trapped beneath the rubble.
The powerful blast occurred in an annex attached to the apartment building in the early hours of Friday. The explosion triggered a major fire and caused part of the structure to collapse, the police statement said.
A group of young men had allegedly been manufacturing explosive devices in the building's basement, the newspapers Het Parool and De Telegraaf cited the fire brigade and witnesses as saying.
The devices were similar to those used in cash machine bombings, the reports said, adding that the suspects are believed to have been preparing for a robbery in Germany.
Amsterdam Mayor Femke Halsema condemned the production of explosives in the middle of a residential neighbourhood, calling it "anti-social."
Since residents apparently knew about the activities, questions are now being raised about whether police were also aware of them, Halsema told broadcaster NOS.
For years, a group from the Netherlands has been held responsible for blowing up cash machines in Germany. Separately, explosive attacks regularly occur in criminal circles targeting flats and company buildings.
"We are trying to track down those who make and plant the explosive devices," Halsema said.
She called preparations for explosive attacks in residential areas a "gigantic" problem.
