A father has been jailed after he sexually abused his daughters from the age of four and let his co-workers gang-rape them for over two decades, it has now been revealed.

The 80-year-old man, who cannot be named for legal reasons, pleaded guilty to 87 charges during an appearance last week at the Townsville District Court, Daily Mail reports. However, the man blamed the decades-long abuse on a "vision" he had of one of his daughters becoming a prostitute and a drug addict. According to him, he subjected his daughter to vaginal, anal, and oral rape at knifepoint in order to "shock" the girl out of following the path he saw in the vision.

According to the Townsville Bulletin, the girls' mother reportedly knew of the abuse and did nothing to intervene or make it stop. That said, the court was shocked to hear of one incident when the father allegedly set the family dog upon one of his daughters. In yet another disturbing revelation, the mother loaned $300 to her daughter, then 15, to pay for an abortion after she was impregnated by her rapist father. She had to eventually pay back the money to her parents. The father also took groups of men to his workplace and let them gang-rape his daughter, it was revealed in court.

A victim impact statement written by one of the abused girls said, "My father is a person I have feared all my life. He has had a lifelong traumatic impact on me. I was just a little girl and could not understand what I had done wrong to warrant such vile treatment, punishment, and threats by my father."

The Townsville District Court (pictured) was shocked to hear of one incident when the father allegedly set the family dog upon one of his daughters. (Google Maps)

The court heard how the woman's whole "world fell apart" and her "life changed forever" after she saw her mother walk in on the abuse and she did nothing to save her.

Furthermore, the devastated daughter claimed the abuse didn't stop until adulthood, with her father raping her even while she was pregnant with her husband's child. The cruel parent would threaten to kill her or the unborn child if she told anyone about the abuse, and would often rape her while her husband was at work.

Speaking for the father, Defence barrister Tom Polley argued that his client regretted what had happened and was extremely remorseful for his actions. However, he was sentenced to 27 years in prison by Judge Lynham. As soon as the verdict was announced, one of the daughters let out a cry from the public gallery. She later told reporters she would carry the trauma at hands of her own father for the rest of her life.