A man is in custody after a house fire in Rouse Hill this morning.
About 12.55am, emergency services were called to Tallawong Road in Rouse Hill following reports that a house was on fire.
Officers attached to Quakers Hill Police Station, Fire and Rescue NSW and NSW Ambulance paramedics attended.
Upon arrival, police observed a 40-year-old man at the rear of the property. Police attempted to restrain the man when he tried to re-enter the burning house. He then armed himself with a knife.
Police attempted to speak with the man, who refused to put down his weapon, resulting in the deployment of a taser and him being sprayed with capsicum spray.
A member of Fire and Rescue NSW is also believed to have been assaulted, however he did not require treatment for any injuries.
The 40-year-old was arrested and conveyed to Blacktown Hospital where he will undergo a medical assessment. He remains under police guard.
The house sustained significant damage, with Fire and Rescue NSW working to extinguish the flames.
Police believe the fire was deliberately lit and a crime scene will be established.
Investigations continue, and further information will be available when it comes to hand.
Anyone with information about this incident is urged to contact Crime Stoppers: 1800 333 000 or https://nsw.crimestoppers.com.au. Information is treated in strict confidence.
