Joe Garza, a 65-year-old man lent his computer to a young family friend who discovered nude photographs of his 10-year-old sister on it.
According to Fort Worth Star-Telegram, the man, Joe Garza, Jr, was charged with possessing child pornography and s*xual abuse of two young children.
After he lent the computer to the family, they confronted Garza with the photos. The family then notified the authorities.
Garza was arrested on March 3. Initially, prosecutors charged him with possessing child pornography and s*xual abuse of the 10-year-old girl.
But on Tuesday they filed additional charges accusing Garza of also abusing the girl's older sister years ago.
Daily Mail UK reports that Garza is being held at Tarrant County Jail with bail set at $145,000.
Authorities said that the saga began weeks ago when the girls' brother had a faulty hard drive on his computer.
That's when the boy asked Garza if he could borrow his computer.
'When he hooked it up, he saw a folder on there,' Domingo Martinez, a Fort Worth police officer assigned to the North Texas Internet Crimes Against Children Task Force, said.
'Curious, he looked at it, and that's when he saw pictures of his sister.'
The young boy then returned the computer to Garza and told his parents. The boy's mother asked her to son borrow the computer once again from Garza so that he could show her the photographs.
The boy then returned the computer to Garza as if nothing happened. The mother, having seen the photos, sent a message to Garza asking to speak with him.
Garza then came over to her house and was shown the photographs.
'They talked for two hours,' Martinez said. 'I don't know if he openly admitted it but he said he has a problem and asked her not to call the police and that he would disappear and not come back.'
With Garza still at her home, the mother texted her older daughter, asking her to notify the police. When the officers arrived at the mother's home, Garza was still there.
Police then began to question him. During questioning, Garza is said to have admitted to s*xually abusing the 10-year-old girl as well as taking photographs and video of the girl.
Garza also confessed to molesting the girl's older sister when she was about 10 or 11 years old, according to a police affidavit.
The older sister corroborated Garza's confession, telling police that she was abused. She said that Garza forced her to wear a blindfold during the abuse, according to police.
The younger sister told police that Garza bought her gifts and gave her money periodically. She said that Garza warned her not to tell her parents.
Police believe that both girls were abused for a period of over a year. Martinez said that police conducted a search of Garza's computer and discovered photos and videos of both girls.
One of the videos shows a girl whose physical description fits that of the older sister. The girl is seen hanging upside down in the dining room area from a white rope.
Police said that a search of Garza's home turned up a swinglike contraption with white rope hanging from it.
Investigators are now trying to determine if there are more potential victims.