Three more Twin Cities women have been charged in connection with an alleged sex-trafficking ring involving young girls and Somali-American gangs -- this time for reportedly threatening and attacking a key witness in the case.

Hawo Osman Ahmed, Ifrah Abdi Yassin and Hamdi Ahmed Mohamud appeared at a detention hearing Tuesday in U.S. District Court in Minneapolis on charges that they had threatened and assaulted a witness identified in an affidavit only as "MA."

Ahmed was ordered held and will be transferred to Nashville to face charges there. A U.S. magistrate judge ordered that Yassin and Mohamud each be released to a halfway house while their cases are pending.

The charges against the women bring the number of people charged in connection with the alleged sex-trafficking ring to 33. In November, the U.S. Attorney's Office for the Middle District of Tennessee announced indictments against 29 people, mostly from the Twin Cities, for allegedly running an interstate human trafficking ring that sold Somali girls -- one as young as 12 -- into prostitution. A 30th suspect was indicted last month.

The suspects, said to be members of three Somali gangs, are alleged to have run a decade-long business that included credit card fraud and burglary -- as well as transporting girls from the Twin Cities to Columbus, Ohio, and Nashville to perform sex acts for money.

The three women accused of threatening the witness were arrested Friday, after the witness called an investigator from Minnesota -- who was in Nashville at the time -- to say she had been assaulted.

Trapped in an elevator

According to the affidavit filed by Heather Weyker, a St. Paul police investigator working on the Gerald Vick Human Trafficking Task Force, MA called her on June 16 "crying and very upset."

MA said she'd been assaulted at her apartment building in Minneapolis. Weyker called Minneapolis police at the scene, who confirmed the reported assault, Weyker said in her affidavit.

The assault occurred, MA said, after she saw Hawo Ahmed pounding on a window. Ahmed allegedly told MA she wanted to fight her for talking about her to another girl.

Ifrah Yassin, who was also there, then told MA that she also wanted to talk to her, saying: "You locked all my [friends] up," according to the affidavit from Weyker.

At that time, MA said, the third person, Hamdi Mohamud, also showed up.

MA said she agreed to fight the three but wanted to go to her apartment to change clothes. The women got into the elevator together.

Once in the elevator, MA said Hawo Ahmed pushed the pause button and hit MA while the others held her. During the altercation, MA said, she was cut by a knife that one of the three was carrying.

Eventually, MA got out the elevator, got a knife from her apartment and went downstairs to go after the women who attacked her, Weyker said.

Police were called, and the fight was broken up.

October trial date

The sex-trafficking investigation began when Somali parents in Minnesota came forward in 2007 with concerns about young girls and gang activity.

Those concerns sparked an investigation by members of the Vick Human Trafficking Task Force, which includes officers from a number of agencies, including the St. Paul Police Department and U.S. Immigration and Customs Enforcement.

The case came to light about 18 months ago, when one of the victims was found by police in the Nashville area. Van Vincent, an assistant U.S. attorney in Nashville, is leading the case and working closely with Weyker. He said an Oct. 4 trial date has been set, although it is possible it will be pushed back.

In her affidavit, Weyker said MA has appeared before a federal grand jury in Tennessee and could be called as a witness at trial. Late last year, Weyker talked about getting young witnesses to come forward in such cases. She earned the victims' trust with hundreds of hours of visits and phone calls, she said.

"I had to be sincere, and I am sincere," she said. "I have to tell them I understand, even though I haven't been through their horror. I tell them I'm here to help."

James Walsh • 612-673-7428