The first signs of a security situation at the Environment Building at 40 Scotts Road came at around 9am when multiple sources told CNA that people were allowed to leave but not enter.
An email sent to employees at about 10am said there was an “emergency situation” and that the building was “under lockdown” but people could leave if they wanted to.
The same information was seen on a sign next to turnstiles on the ground floor when CNA arrived at the scene later in the morning.
Minister for Sustainability and the Environment Grace Fu later wrote on Facebook that she received news while overseas about a “security situation” at the building.
“Police had worked with security officers on premises for preliminary checks and no threat items were found,” she said at about 1pm.
“I’m monitoring the developments closely from here and am in constant contact with my colleagues.”
Another email sent to employees at about 12.20pm said that the building would be closed for the rest of the week.