A man is in hospital after suffering a medical episode while being arrested in Sydney’s west.

Emergency services arrived at a home on Nipper St in Homebush about 8.30am on Monday after receiving reports of an alleged domestic violence incident.

Officers then gained entry into a nearby unit block and arrested a 52-year-old man with the use of OC (Oleoresin Capsicum) spray.

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NSW Police said the arrest was to “prevent a beach of the peace”.

Shortly after the man then suffered a medical episode and was treated by paramedics before being taken to Westmead Hospital in a critical condition.

Investigations into the initial incident have been launched alongside a critical incident team.

“The investigation will be subject of an independent review by the Professional Standards Command and oversight by the Law Enforcement Conduct Commission,” said police.

Anyone with information has been urged to contact Crime Stoppers.