Girl, 14, involved in NSW armed robbery

A 14-year-old girl is due to face children's court over her alleged involvement in the armed robbery and assault of a man in Sydney's inner west.

It's alleged a 37-year-old man and the girl, armed with what's believed to be a taser, assaulted a 24-year-old man at a Newtown home on Tuesday night before stealing his watch and jewellery, police said.

During a raid at a Newtown home on Wednesday, police arrested the pair and seized prohibited firearms, ammunition, prohibited drugs, a sum of cash and alleged stolen property.

The pair were remanded in police custody with the 37-year-old man due to face Newtown Local Court and the 14-year-old girl due to face children's court on Thursday.