Mayor A.J. Holloway has been admitted to an alcohol treatment facility in Hattiesburg.
The city, in a news release posted on its website, said Holloway checked himself into the facility Thursday afternoon.
Holloway has appointed Ward 2 Councilman Felix Gines as acting mayor while he's being treated.
The 75-year-old Holloway is in his sixth term as Biloxi's mayor. He is the city's longest-serving mayor and was elected to his first-term in 1993. Prior to that, he was elected to the City Council in 1989.