A top anchorwoman on Iranian state-run television, who has been jailed in the U.S. as a “material witness” in a criminal case, has not been charged with a crime, the Associated Press reported Saturday. Marzieh Hashemi, a U.S.-born American citizen whose birth name is Melanie Franklin, was detained Sunday in St. Louis by federal authorities. Hashemi, who was in the U.S. visiting family and filming a documentary on Black Lives Matter, is poised to be released after giving grand jury testimony, officials reportedly said. A federal judge has ordered parts of Hashemi’s case to be unsealed. But details of the criminal case in which Hashemi is named as a witness are not available, per the AP. It’s unclear how long Hashemi, who resides in Tehran, will testify. Under federal law, judges may detain witnesses if government attorneys can show that their testimony is extraordinarily valuable to a criminal investigation. Prosecutors must also prove that this witness poses a flight risk and would probably not respond to a subpoena, the AP explains.