Police are investigating the "horrendous" assault of an elderly woman in her Sydney home, after bank workers noticed her injuries and raised the alarm.
Investigators believe the 78-year-old was assaulted in her Toongabbie home, about 30km west of the CBD, sometime overnight.
"This is horrendous, it is not something that occurs frequently in this area, it is something that is a great concern to us," Superintendent Gary Merryweather said this afternoon.
Bank workers noticed the woman's "significant" injuries and called emergency services after she went to the Seven Hills branch this afternoon to cancel her credit cards.
"The bank workers were very much alarmed at the injuries they saw and did an excellent job at attending to her," Supt Merryweather said.
Paramedics treated the woman and took her to Westmead Hospital, where she remains in a serious but stable condition.
Police have launched an investigation into the assault and have urged any witnesses to come forward.
There are no obvious signs of forced entry at the home and police have not yet established a motive for the attack.
"We're looking at quite a brutal attack, that is why the help of the community is important. If anyone may suspect someone that has done something a bit suspicious or a bit odd, they should contact Crime Stoppers immediately," Supt Merryweather said.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000.