The son of a couple found dead inside their burger bar in Sydney’s west has been charged with their murder.

Officers were called to the shop on Oxford Street, Cambridge Park, near Penrith, after reports of an assault about 9.40am on Saturday.

Hoa Tek Chiem, 69, and Heang Kim Gau, 68, were found with “significant injuries” inside their family-run Buzzy Bee’s Burger House by another of their sons.

Their 31-year-old son Allan Chiem was arrested at a home at Canley Heights, 30 kilometres west of the CBD, at about 12.30am on Sunday.

Chiem was taken to Fairfield Police Station where he was charged with two counts of murder.

He was refused bail to appear at Parramatta Local Court later on Sunday.

Detective Superintendent Michael Cantrell said officers arrived to a “confronting scene”.

“Obviously the welfare of our officers is being addressed, and we have systems in place for that,” he said in Sydney on Saturday.

Cantrell said footage possibly relating to the incident had been posted on social media. It apparently shows a man dressed in black in the area, with one witness reporting he was on the roofs of the Cambridge Park shops before jumping to the ground.

“I’m aware that there is footage around, and it’s been through social media, and we’re looking into that and looking at all lines of inquiry,” he said.

-with AAP