Baltimore's oldest and largest nonprofit AIDS service organization will close its doors November 26—the day before Thanksgiving, local CBS affiliate WJZ-TV reports.

For 25 years, the Health Education Resources Organization (HERO) has offered mental and physical health care, housing services, drug abuse counseling and legal services to Baltimore residents living with HIV. With many of HERO's estimated 3,000 clients currently homeless, there is concern about where they will go once the organization is gone.

According to the report, the reason for the closure remains unknown.