Police had been known as to Charles Street in Liverpool shortly after 2am in a single day, after studies a shot had been heard.
They surrounded a block of models and known as in specialist officers, together with negotiators.
A lady was arrested at about 2.15am when she left the constructing.
The operation ended at about 5.40am when two different girls and two males had been arrested.
There have been no studies of harm.
Police are set to execute a criminal offense scene warrant on the scene.
Anyone with info is urged to name Crime Stoppers on 1800 333 000.
Source: www.9news.com.au
