A critical incident investigation is underway after a man allegedly attempted self harm in police custody at Green Valley overnight, NSW Police say.
The 32-year-old man was being held in the holding dock at Green Valley Police Station in relation to an alleged domestic violence-related kidnapping yesterday today.
About 1.20am today tomorrow, officers found the man unresponsive.
Police rendered first aid before he was taken to Liverpool Hospital where he is reported to be in a stable condition.
The man remains under police guard.
A critical incident team from South West Metropolitan Region will now investigate all circumstances surrounding the incident.
That investigation will be subject to independent review.
Police are urging anyone with information in relation to this incident to call Crime Stopers.