Three seriously injured after knife-wielding masked intruders allegedly storm Illawarra home in southeast NSW

Three men have been seriously injured after masked intruders armed with a knife allegedly stormed a home in southeast NSW before dawn.

Police allege four men wearing balaclavas — one armed with a knife — forced their way into a home on Mummunga Close in Flinders, in the Illawarra region, about 3.40am on Sunday.

The group allegedly broke into a converted garage and assaulted a 20-year-old man.

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When three other occupants — two men aged 19 and 43, and a 37-year-old woman — attempted to intervene, they were also attacked.

The alleged intruders fled shortly afterwards.

NSW Ambulance paramedics treated the 43-year-old man for stab wounds to the head and chest, the 20-year-old man for stab wounds to the leg and stomach, and the 19-year-old man for significant facial injuries.

All of them were rushed to hospital in a serious condition.

A crime scene has been established as investigations continue.

Anyone with information is urged to contact Lake Illawarra Police District or Crime Stoppers.