NSW Police said the boys’ 42-year-old mother was also found at the scene with stab wounds, and was taken to hospital in a critical but stable condition.
Smith was released from hospital on Friday and taken to Parramatta Police Station, where she was charged with two counts of domestic violence-related murder, police said.
She was refused bail to appear at Parramatta Local Court today.
“The information I’ve been given so far is ... the employee was let go from a NSW government agency,” Minns said on Friday.
“It was challenged in the Industrial Relations Commission, the original decision of the government department was upheld, and I believe it was handled appropriately.”
Smith’s personal Facebook page is filled with photos of her and the children together, showing them on frequent bushwalks and beach visits.
The premier said government departments would co-operate with any of the “major inquiries” he forecast into the tragedy.
“Both from the homicide squad and the NSW Police as well as potentially the Coroner’s Court as well,” Minns said.
“If new information comes to light, of course government agencies and the NSW Government will supply that to any independent investigation that takes place. This is a very serious alleged crime.”
The boys’ father Nick Smith, who does not live at the Blue Mountains home, this week expressed disbelief at the tragedy while also calling for privacy.
”The loss of our two beautiful boys has caused unimaginable pain and distress,” he said in a statement.
”Russell and Ben were happy, funny, outgoing boys and were very much loved by their family and friends.”