OSLO • Norwegian police set off a controlled explosion of a "bomb-like device" in central Oslo early yesterday, and are holding a suspect in custody in an investigation led by security police.
A Reuters reporter described a loud bang shortly after Oslo's bomb squad arrived with a remote-controlled robot once the area was cordoned off by police late on Saturday night.
"The noise from the blast was louder than our explosives themselves would cause," a police spokesman said, adding that further investigation was needed to find out if the device had contained explosives.
The device, about 30cm across, seemed capable of causing only limited damage. Forensics experts will examine fragments to figure out what it was.
The authorities still do not know what the object was, Mr Svein Arild Jorundland, a police commander at the site, told reporters. "There was a police patrol that came across a man they became interested in. In connection with him, they found a box with content that police believe was suspicious," he said.
Police across the Nordic region have been on heightened alert after a truck ploughed into a crowd in Stockholm last Friday. Four people were killed and 15 injured in what police called an apparent terror attack.
Norwegian police detained a suspect but declined to give information about his identity.
Norway's police security service, PST, said in a tweet that it had taken over the investigation from local police. "We are in a very early phase of the investigation," PST spokesman Martin Bernsen said.
Police took away cordons put up overnight in the Groenland area and residents resumed their normal Sunday activities, with shops and cafes open. There was no sign of police at the site.
The Groenland area is a multi-ethnic neighbourhood that is home to popular bars and restaurants, several mosques and the city's main police station. The police station is less than a kilometre away from where the device was found.
In 2011, right-wing extremist Anders Behring Breivik set off a car bomb in Oslo that killed eight people and went on a shooting rampage that killed 69 people on a nearby island.