The Cube in Birmingham was evacuated after a security alert was raised when the boss of one of the businesses housed in the complex received an email threat.
Police searched the area following the discovery of two suspicious packages in the building, which was evacuated.
Birmingham Police tweeted following the evacuation: "The Cube building on Commercial Street remains cordoned off following an earlier security alert. Officers still searching premises."
Reporter Stuart Bailey told regional station Free Radio: "I understand that a senior boss at one of the businesses in The Cube received some kind of threat by text or email.
"The staff here are huddled around outside - they've been told to expect an update at 12:30pm."
The Cube's official Twitter account said: "We have been evacuated as a precaution but @WMPolice are searching the building thoroughly.
"Police dogs are on scene and are giving us a check-over. Hoping to be given the all clear soon."
The Cube is an extension of the city's flagship canalside development, the Mailbox, and is home to Marco Pierre White's restaurant and Adee Phelan's salon, who used to be the hairdresser opf David Beckham.