Police shut down Melbourne CBD streets

The man was arrested and taken to hospital for observation under police guard. Police said the scene had since been declared safe.

Emergency service personnel earlier responded to reports the man was behaving erratically at the building while in possession of petrol cans and other hazardous substances.

Witnesses Sam Di Palma and Daniel Safstrom said they saw a man in the building with a full trolley and officers were trying to talk to him.

The building houses offices for CGU Insurance, the Commonwealth Director of Public Prosecutions, Court Services Victoria and legal firms including Gordon Legal and Baker McKenzie.