A lavish home has been invaded in a terrifying armed attack while two boys were inside.

Three men carrying a firearm allegedly burst through the front door of the property on Ardennes Ave at Edmondson Park, in the southwest of Sydney, at about 1.45am on Monday.

WATCH THE VIDEO ABOVE: South West Sydney home invasion.

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“They threatened and assaulted a 48-year-old man and a 12-year-old boy,” NSW Police said.

“An 11-year-old boy was also inside the house at the time.”

The invaders allegedly stole several possessions from the home, including jewellery.

They then fled in the unknown vehicle they arrived in.

The 48-year-old victim suffered facial injuries during the alleged assault.

He was treated at the scene by NSW Ambulance paramedics.

The two children were uninjured.

An ongoing investigation in underway, but no arrests have been made at this stage.