The man responsible for sending a Sydney Airport terminal into lockdown allegedly assaulted multiple people, including a police officer, the following day while he was out on bail.

Nicholas Teplin, 41, allegedly approached a 45-year-old man and punched him in the face at the Suburban Concourse of Central Railway Station in Sydney’s CBD about 4.40pm on Thursday.

The victim fell to the floor and suffered a nose bleed, while Teplin allegedly went up to two other men and struck them both in the head.

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Teplin then allegedly approached a 20-year-old man and attempted to grab his bag from his shoulder before police arrived and arrested the alleged offender.

Whilst in custody, Teplin allegedly assaulted a male police officer by pushing him in the chest.

The Victorian man was charged with multiple offences including affray, assault occasioning actual bodily harm and assaulting a police officer.

Teplin was out on bail at the time of the alleged assaults following an incident the day prior at Sydney Airport’s domestic terminal.

He was approached by officers about 6am on Wednesday following “a report of suspicious behaviour” at the bag check-in counters, Australia Federal Policed (AFP) acting commander Scott Raven said.

He allegedly became verbally and physically aggressive towards AFP officers and was arrested.

During his arrest an AFP firearm was discharged.

The terminal was reportedly sent into lockdown however this has been denied by the AFP.

They would also not comment on whether Teplin reached for the gun at any point or who was in possession of the firearm when the shots were fired.

Teplin was arrested and charged with obstructing and hindering a Commonwealth official, and creating a disturbance at an airport.

He was granted bail to appear in court in September.

In relation to the alleged assaults at Central Railway Station, Teplin was refused bail to appear via video link in court on Friday.