Lucia Pinochet "was the target of an international arrest warrant issued by a Chilean judge," and was detained, presidential spokesman Osvaldo Puccio said.
U.S. officials said Lucia Pinochet, 60, arrived with a son at Dulles International Airport outside Washington on a flight from Argentina at 7 a.m., and was detained but was not under arrest.
"We're evaluating what to do next. There are a couple of different options," said Marc Raimondi, a spokesman for Immigration and Customs Enforcement, an agency of the Department of Homeland Security.
Chilean Foreign Minister Ignacio Walker said he ordered his country's consul in Washington, Felipe Cousino, to try to interview Lucia Pinochet.
He said she apparently has three choices: to have U.S. authorities send her back to Argentina; to voluntarily return to Chile and appear at court; or to go back to Argentina by herself, "which would open the way for an extradition request by Chile."
Walker said "the government has no recommendation to make on this. Our interest is that the judicial resolution be obeyed."
She apparently traveled to neighboring Argentina on Sunday, hours before she and other relatives were due to appear in court to be served notice of her indictment on charges of tax evasion and using a false passport.
Judge Carlos Cerda indicted Pinochet's wife, also named Lucia, and their grown children Veronica, Jacqueline and Marco Antonio in the case.
Charges also were filed against Marco Antonio's wife and a lawyer and a secretary for Pinochet. All are free on bail.
The case stems from a scandal that erupted in Washington itself.
A July 2004 report by Senate investigators alleged that Pinochet had worked with managers of the Riggs Bank in Washington to set up phony offshore companies to hide the existence of funds. It said he had about $8 million at the bank.
A subsequent judicial investigation in Chile determined that Pinochet had deposited as much as $28 million in accounts in several countries.
In a communique last year, Pinochet explained his foreign accounts by saying that "for reasons of prudence, because I knew I would be the target of persecution and political harassment, I delivered to professional international institutions the savings of my entire life. If some tax difference occurred, my advisers have paid every thing that was owed."
Lucia Pinochet, the daughter, was the only of those charged that dodged receipt of the judge's summons. She did not join other family members gathered to meet court officials with the summons, nor did she later turn up in court.
Marco Antonio Pinochet denied that the family committed any crime, and said "but we will only talk once we are given the chance to defend ourselves."
And his brother, Augusto, said his father "is a very old man and feels this is his fault, although is not."
"He feels pain because it's his family that is being affected," he told the Santiago daily Las Ultimas Noticias.