VIENNA (Reuters) - Austrian police are investigating a man they suspect imprisoned, beat and sexually abused his two daughters over a 40-year period, they said Thursday.

The 85-year-old Austrian, from a village near the northern town of Braunau, kept the women locked in a small kitchen with only a wooden bench as a bed, police said.

"The accused repeatedly threatened to kill them and threatened them with weapons," the police department of the province of Upper Austria said in a statement.

The man banned his daughters from having "any social contact," the statement added. It was not immediately clear if they were confined all the time.

The description has echoes of the Josef Fritzl incest case which rocked Austria three years ago. Fritzl fathered seven children with his incarcerated daughter before being imprisoned for life in 2009 aged 74.

Police said the women, now aged 53 and 45, were suffering from "mental deficiencies" and were being sheltered and treated after their ordeal.

They escaped in May when the father tried to rape the elder daughter and she fought back, injuring him as he fell to the ground. A social worker found the father two days later and reported the alleged abuse to the authorities.

The father is now bed-ridden in hospital but is "mentally active" for his age, police said.

Police did not say whether the daughters gave birth to children by their father. The police statement, which did not name the man, said he abused them from 1970 to May 2011 in the village near the German border.

(Reporting by Sylvia Westall; editing by Rosalind Russell)

(This story was corrected to change the age of suspect to 85 after an official correction from Austrian police)

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