Tanzania's deputy health minister Hamis Kingwangala has ordered three men who he accused of being gay to report to police for questioning - or risk arrest, reports the BBC's Sammy Awami from the main city Dar es Salaam.
He said the three were "spreading" homosexual activity through social media, in violation of the law.
Gay sex is illegal in Tanzania and punishable by up to 30 years in prison.
Last year, Tanzania's health
The government also threatened to ban groups that "promote" the rights of lesbian, gay, bisexual and transgender (LGBT) people.