Reuters
Company spokesman Even Westerveld confirmed to Reuters that 4,000 members of staff evacuated the building but employees were soon allowed back in.
"The police has told us that it is safe to return to the building, so we're following that advice. The threat is called off," he said, without elaborating on any further details.
DNB has total combined assets of more than 1.9 trillion Norwegian krone and a market capitalisation 196 billion Norwegian krone.