PolAir hunt after man stabbed during alleged home invasion on Mountfort St, Lalor Park

A man was rushed to hospital after a knife went through his back following an alleged break and enter in Lalor Park.

NSW Police PolAir on a night patrol across Sydney.

A man has been hospitalised after a knife went through his back following an alleged break and enter in western Sydney overnight.

Police allege that just after midnight on Thursday, a group of armed people forced their way into a granny flat on Mountfort St in Lalor Park and confronted a 20-year-old man inside.

The man was allegedly stabbed in the back and fled the scene to seek help from a neighbour when emergency services were called.

In response to the call, police tasked PolAir and the Dog Unit to go out and conduct a search in the area with hopes of catching the alleged offenders.

Their search resulted in the arrests of four teenagers aged 16, 17, 18 and 19 that night.

Mountfort Street in Lalor Park, NSW. Picture: Google Maps

The young men were taken to Blacktown Police Station where they assisted police with inquiries.

Police were told that an altercation ensued between the 20-year-old man, who was the sole occupant of the home, and the group, resulting in the man suffering facial injuries and a stab wound to the back.

They could not confirm whether or not the teens and the occupant of the home were known to each other.

Officers from Blacktown Police Area Command attended and established a crime scene.

Inquiries continue.