The Uzbek Prosecutor-General's Office says Gulnara Karimova, eldest daughter of the late longtime President Islam Karimov, is in custody following a 2015 conviction and faces additional charges in a continuing investigation.

The July 28 statement marked the first time authorities in the tightly controlled Central Asian country have revealed details about the status of Karimova, who has long been rumored to be under strict house arrest in the capital, Tashkent.

It came amid steps by President Shavkat Mirziyaev, who replaced Karimov after his death was announced in September and was subsequently elected, to decrease the country's isolation.

Karimova, 45, was once a high-profile socialite, fashion designer, pop singer, and ambassador to United Nations agencies in Geneva who was seen as a potential successor to her father, the autocrat who ruled for a quarter-century.

But she vanished from sight as she found herself at the center of a financial-crimes probe in Uzbekistan in which many of her associates have been jailed, and she has also been tied to ongoing money-laundering investigations in Sweden and Switzerland.

The statement by the Prosecutor-General's Office said that Karimova was sentenced to five years of "restricted freedom" in 2015 after she and several associates were convicted of crimes including extortion, embezzlement, and tax evasion.

Karimova has additionally been charged with several other crimes, including financial misdeeds, forgery, and money laundering, and the investigation continues, the statement said.

It said she has been ordered held in custody in connection with those charges, but it did not specify what form of custody.

Multiple previous reports have indicated she has been under house arrest since 2014.

In the statement, the Prosecutor-General's Office said it is seeking to impound $1.5 billion worth of assets owned by Karimova in Britain, France, Germany, Hong Kong, Ireland, Latvia, Malta, Russia, Spain, Switzerland, Sweden, and the United Arab Emirates.

It alleged that Karimova illegally obtained assets worth more than $590 million and received some $870 million in kickbacks.

The Prosecutor-General's Office claimed that in total, the actions of Karimova and her associates had cost the Uzbek state about $1 billion or $2 billion, depending on which of two conflicting figures in the statement is accurate.

In 2016, the U.S. Justice Department placed a seizure order on nearly $600 million stemming from a suspected bribery scheme allegedly involving Karimova and a shakedown of major multinational telecommunications companies.

In the absence of official information about Karimova's fate, rumors, reports, and speculation have swirled for years.

Neither Karimova nor her children were present at her father's funeral in September.

A Twitter account published a series of posts in October suggesting that Karimova was the author of the tweets, but an investigation by RFE/RL's Uzbek Service found that the person or group tweeting from the handle @Zabitaya1972 is merely posing as her.

In December, media reports quoted Karimova's Geneva-based lawyer, Gregoire Mangeat, as saying that Swiss prosecutors were allowed to question Karimova for a total of 23 hours on December 9-10 in Uzbekistan's capital, Tashkent.

Earlier the same month, Karimova's son told the BBC his mother was being held in a "two-to-three room annex" to her main property in Tashkent.

The son, whose name is also Islam Karimov and who lives in London, said that Karimova was sane, but voiced concern about her health after what he said were years of isolation "without any even basic human rights."