(CNN) -- A 70-year-old man in Saudi Arabia is disputing claims his new bride is 15 years old, and says her family has ripped him off for the large dowry he paid for the union.
Human rights workers say the bride is a teenager and are outraged about the situation.
CNN interviewed the man Tuesday, who said he paid a dowry to the girl's parents for the equivalent of $20,000. The marriage came to light when the man complained to a local official after his new wife left him, saying the girl's family had taken her back and he'd been ripped off. He also claimed that he thought she was 25 years old.
He refused to provide his name to CNN.
"She is not 15 as everybody claims," he said. "She's 25 years old and she's mature enough to make her own decisions... I was fooled by the girl's family."
In Saudi Arabia, there is no law that stipulates a minimum age for marriage.
Human rights workers say they believe there was a fight between the teen and the man, and she ran back to her family.
Her father is believed to be Yemeni, her mother Saudi, the rights workers told CNN.
She is from Al-Hurath village in Jizan province, in southwestern Saudi Arabia near the border with Yemen, according to Dr. Hadi Al-Yami, the head of the Asir branch of the Human Rights Commission. The group is backed by the Saudi government.
The commission sent an investigator to the courthouse in Al-Hurath, Al-Yami said, and is planning to offer the girl and her family as much help as she's able to receive, particularly legal help in case the courts require her to formally dispute the marriage.
Dr. Suhaila Zein al-Abedin of the Saudi National Association for Human Rights -- also a government-backed group -- voiced concern not only about the age difference, but the circumstances of the marriage.
"When you consider the very large difference in age, it looks more like this was not a marriage, but like the girl was sold," al-Abedin said. "The girl's parents need to be held responsible for this."
Some groups, such as the HRC, advocate for setting a minimum age for marriage, though they've not said what age. The group proposes that anyone younger than 18 who wants to get married should get a court's consent.
Extremely conservative religious scholars have opposed a law that would govern the age to marry.
Messages on social media reflect frustration with that opposition.
Prominent Egyptian activist Mona Eltahawy tweeted, "It's only when there's enough public outrage that we can fight #childmarriage. We are not angry enough to help that 15 y/o & others like her."
Yemeni activist NoonArabia tweeted, "#ChildMarriage is a violation of human rights http://www.humanrightsdefence.org/child-marriage-as-an-human-rights-issue.html ... #RunAwayBride #PTs."
Other Egyptians took to the Web.
Kareem Bassem tweeted, "#ChildMarriage is a result of dehumanizing female humans and degrading them to 'treats' in alleged paradise. Fight dehumanization!"
Related: 11-year-old girl married to 40-year-old man
CNN's Salma Abdelaziz and Ashley Fantz contributed to this report.