NSW detectives are investigating the tragic deaths of twin girls, aged three, who died in a house fire in the NSW South West Slopes region.

NSW Police said emergency services were called to a home on Mayday Road in Batlow about 11am on Monday after reports of a house fire.

Fire and Rescue NSW were able to pull the girls from the house but despite efforts by first responders, the girls died at the scene.

Firefighters had to break down locked doors to rescue three-year-old sisters, Aisha and Lailani.

Paramedics desperately tried to save the badly burnt children, but they died at the scene.

Their mother Tanyka Ford and five-year-old son were in the backyard when the property went up in flames.

Neighbour Carol Flannery told the ABC she was devastated by the news.

“They were born early and poor parents had to be in hospital with them in Canberra and now this,” she said.

“I was just shocked, beautiful little girls – my heart goes out to the parents and grandparents.”

The ABC reported the twins’ mother and an older sibling aged five were outside the home when the fire took hold.

The twin girls were believed to be occupants of the home.

Police were door knocking neighbours on the street throughout Monday afternoon. Photo: Channel Nine

The children’s grandmother, Michelle Ford, posted a tribute on her Facebook page on Monday night.

“RIP Nannys little angels miss you so much,” it said.

Local police have established a crime scene and will be assisted by the State Crime Command’s Financial Crimes Squad’s Arson Unit.

Superintendent Bob Noble said police were speaking to the family and neighbours as part of the investigation.

“There are a number of witnesses we are speaking to and we are canvassing the streets and surrounds,” he said.

“It’s a terribly tragic event for two young girls who lost their lives in awful circumstances.”

The cause of the blaze remains unclear, but detectives are yet to determine whether it’s suspicious.

“We are keeping an open mind as to the cause of the fire,” he said.

A report will be prepared for the Coroner.

-with AAP