Elderly man dies after freezing night trapped in trench

Perry Duffin and Hannah Higgins

A 91-year-old man has died after falling into a trench in his backyard in Sydney's west and spending the night stranded in the cold.

He lived alone in his Glenmore Park home and was found alive by his son on Friday morning.

Police believe he may have spent the night trapped in the trench in chilly conditions.

Paramedics worked to stabilise the injured man when they arrived about 8am but he died shortly after.

The man was still alive when he was found this morning. Photo: 7 News

"I could cry, actually, just thinking of him lying alone in that trench," a neighbour, who asked not to be identified, told AAP.

"It's such an awful thing for his son to find him."

The neighbour said she believes the elderly man was having plumbing work done in his backyard.

The man had moved to the area just over two years ago, the neighbour said, and his wife died suddenly shortly after.

"They still hadn't unpacked the boxes," she said.

"I never saw a great deal of him, I'd only say hello as I'd pass by."

Excavations were underway in the backyard of the home and it's not yet known how long he was trapped in the trench.

Police do not consider the death suspicious but a report will be prepared for the coroner.

He died during efforts to remove him from the trench. Photo: 7 News

His death comes just days after an elderly couple were found dead in their north Sydney mansion.

Police urged family, friends and neighbours of elderly people to put away their smart phones and check in.

"This is an opportunity to reflect on this tragedy and think about our elderly parents and neighbours and what we can do as a community and as individuals to prevent a recurrence of this terrible event," NSW Police said in a statement on Facebook.