When Yousef Goba’s scheme to abduct an underage female relative and extort money from her family failed, he sold his young victim into marriage in Yemen, according to investigators.

In a case that stretches from Buffalo to the Middle East, Goba is accused of taking the girl hostage, threatening her safety and ultimately selling her to another family member.

Goba, 43, is a U.S. citizen and the brother of Lackawanna Six [convicted Muslim terror group] member Yahya Goba, two sources close to the case said Monday. Arrested in New York City earlier this month, he is accused of abducting the girl two years ago and holding her in Yemen until the extortion plot fell apart.

“Goba has married the victim child off to his brother-in-law,” the FBI said in court papers detailing his alleged scheme, “and the victim child and her husband are residing in the village of Qoaz, a very small village in Yemen.”

The allegations against Goba are rooted in his family relationship to the girl’s mother and father and siblings. All of them, except the father, are U.S. citizens.

The mother – who has since divorced her husband, remarried and is living in Yemen – took the children to Yemen in September 2013 to live temporarily so the father could save money while working here, according to court papers.

The following summer, after spending time with the father’s family in Yemen, the mother and children moved in with Goba, according to the FBI.

When they tried to leave, the defendant allowed the mother and the other children to depart, but not the girl.

“Goba would not allow the victim child to leave,” the FBI said in its complaint.

At that point, according to investigators, Goba began using text messages and phone calls to the father to demand money in return for the girl’s release.

“At first, Goba demanded $3,000,” the FBI said. “Goba, however, ultimately demanded that the victim father pay him $12,000.”

Throughout the scheme, investigators say, Goba threatened to marry off the girl to a Yemeni national willing to pay for her. They also claim Goba sent the father a photo of the girl pointing to a wedding cake and a second picture of her with a ring on her finger.

“Goba sent a text message to the victim father telling him that everyone wants to marry the victim child and that these individuals offered to pay Goba for the marriage,” according to court papers, which do not identify the girl and her family.

Defense lawyer Thomas C. Farley and Assistant U.S. Attorneys Timothy C. Lynch and Wei Xiang declined to comment Monday. Goba appeared Monday before U.S. Magistrate Judge Michael J. Roemer and will be back in court Friday for a bail hearing.

“He presents a serious risk of flight and a safety risk to the minor child,” Xiang told Roemer on Monday.

Sources said there appears to be no connection between Goba’s case and his brother’s involvement with the Lackawanna Six.

Yahya Goba, described by prosecutors as the ringleader of the Lackawanna Six, was sentenced in 2003 to 10 years in prison after admitting he trained at an al-Qaida camp in Afghanistan in 2001.