MOSCOW — The authoritarian president of Uzbekistan, Islam Karimov, who has ruled the isolated Central Asian country for more than 25 years using old Soviet methods like forced labor for cotton harvesting, has been hospitalized with a stroke, his younger daughter announced Monday on Facebook.

Later on Monday, Ferghana, an Uzbek website banned at home since 2005, reported that Mr. Karimov had died in the afternoon, citing sources outside the government. The report was widely repeated by independent news outlets in Russia.

There was no official confirmation, however, and Russian outlets, such as the state-run RIA Novosti agency, quoted unidentified government officials in Uzbekistan as saying that the president remained alive and in stable condition.

The nightly news on the main Uzbekistan television channel did not refer to the story at all, mentioning the president as the active leader.