A man wheeled a shopping trolley loaded with fireworks and jerry cans full of gasoline into a busy office complex in northern Australia's largest city today, setting off a blast and fire that injured at least seven people, authorities said.
A motive for the attack was not immediately known. The head of the insurance office that was targeted said it appeared to have been a random event.
Police said a man was taken into custody near the scene after giving himself up to police near the scene soon after the blast, which went off in the Territory Insurance Office that is part of a shopping complex in a busy part of downtown Darwin.
Witnesses described a large booming noise and sounds like gunshots going off, before seeing smoke billowing from the building and people stumbling out. Seven people were taken to hospital, including one police officer who suffered smoke inhalation.
Police commander Rob Kendrick said none of the injuries was life-threatening.
Darwin is the capital city of the Northern Territory, a vast and sparsely populated Outback region. Parts of downtown were cordoned off after the blast as emergency crews arrived and an investigation was launched.
Fire brigade officer Dave Lines said it appeared someone had pushed a trolley with three cans of gasoline and some fireworks into the building. A fire had taken hold after the blast, but was suppressed by the building's sprinkler system and extinguished by firefighters, he said.
Richard Harding, the insurance company's CEO, said it had received no threats or warnings before the explosion.
"At this stage it appears to be a random event, a person has walked into the branch and ignited some petrol," Harding told Australian Broadcasting Corp. radio.