The Uzbek Prosecutor-General's Office has launched a criminal case into the disappearance of Nurmukhammad Sodiqov, a former close associate of Gulnara Karimova, the daughter of Uzbek President Islam Karimov.
Officials said the probe would focus on charges of abduction and abuse of office, without elaborating.
In a call to RFE/RL's Uzbek Service on November 6, Anvar Makhatov, who identified himself as Sodiqov's brother in law, alleged that Sodiqov had been abducted by Karimova's "people" in January.
On Twitter the same day, Karimova denied Sodiqov had long been missing, saying he was at home.
Earlier this week, Karimova said her former security officers had been arrested by security officials.
Last weekend, Karimova accused the chief of the country's National Security Service, Rustam Inoyatov, of blocking her path to the presidency.
Meanwhile, several Karimova-controlled media outlets have been taken off the air and her media group's bank accounts have been frozen.