A gunman who killed one person at a sign-making business in western Sydney has died from a self-inflicted gunshot wound.

On Monday morning, police from New South Wales responded to reports of a shooting at the Inline National Signage factory in Ingleburn.

Police found three men with gunshot wounds upon arrival. A 43-year-old man died at the scene and the two others were taken to Liverpool Hospital for treatment. 

A stand-off between the police and the gunman then ensued for around six hours. Three people had been inside the building for the duration of the stand-off but they emerged on Monday afternoon unharmed. The gunman was found dead inside the building.

The incident on Monday brought the whole area in Ingleburn to a standstill.

After arriving at the industrial site, heavily armed officers surrounded the sign-making building and closed off nearby roads.

During the stand-off, Detective Inspector Mark Brett told a news conference that the operation was at a “delicate stage”.

He added that “tactical operations unit negotiators” were working at the scene.

A man, who was not the gunman, was arrested for allegedly hindering the operation. 

At around 5pm, police entered the building and found the 33-year-old gunman with a self-inflicted gunshot wound, said Detective Inspector Brett.

He added that he had been using a “long-arm weapon”.

Officers then exited the building with the three people. It was not clear whether they had been held hostage by the gunman or whether they had been hiding.

Additional reporting by PA

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