A man has been charged with murder after a young woman was allegedly stabbed to death in Western Sydney.
The 21-year-old woman was allegedly stabbed twice in the chest about 1.40pm on Monday at a home on the Great Western Hwy at Kingswood.
Two other people who were present called triple-0.
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Paramedics treated the woman, but she died at the scene.
She is yet to be formally identified.
A man was seen running from the complex, Superintendent Trent King said, sparking a police search.
Police allege the man and woman were in a relationship.
Officers arrested a 22-year-old man at Derby Street, Penrith, about 7.10pm.
He has been taken to Penrith Police Station, where he was charged with murder domestic violence.
The man is expected to face Penrith court on Tuesday.
A crime scene was established at the unit complex, with police seen scouring through the home for evidence.
Anyone with information is urged to call Crime Stoppers.
If you or someone you know is impacted by sexual assault, domestic or family violence, call 1800RESPECT on 1800 737 732 or visit 1800RESPECT.org.au.
In an emergency, call 000.
Advice and counselling for men concerned about their use of family violence: Men’s Referral Service, 1300 766 491.