Protesters were calling on President Cyril Ramaphosa to publicly condemn what they called Dar es Salaam’s “assault on the civil liberties of queer Tanzanians”.
They also appealed to Ramaphosa to offer asylum to “those who are facing arrest for simply being who they are”.
Faith Mathole, amandla.mobi spokesperson, said: “Paul Makonda [the regional commissioner of Dar es Salaam] had deployed a surveillance squad to track down queer people on social media.”
Homosexuality is illegal in Tanzania and anti-gay actions had escalated since President John Magufuli’s inauguration in 2015, she said.
“Queer people have been forced to hide their identities and sexuality.”
Makonda recently made a statement saying “I prefer to anger those countries than to anger God”, in response to other countries’ protests at Tanzania’s gay rights record.
Mathole claimed: “Recently there had been reports that the names of 18,000 people had been handed to the Tanzanian government on suspicion of being queer.
“They had even gone as far as shutting down HIV clinics on the basis of them supposedly promoting homosexuality.”
Clio Koopman, amandla.mobi campaigner, said: “The situation in Tanzania has reached a crisis point. Queers fear for their freedom.
“South Africans could not sit back and allow this anti-queer witch hunt to continue.
“President Ramaphosa had acknowledged that the LGBTI community are amongst the most vulnerable and marginalised.”
She was referring to remarks Ramaphosa made in November 2017 at the Feather Awards “about the need to stop the suffering, discrimination, violence, and abuse of the queer community”.
READ MORE: ACDP in gay flag furore
“We must hold the president accountable for his commitments to queer rights by demanding he stand in solidarity with queer people in Tanzania.
“We understand the pain of not being able to be ourselves. We are telling the South African government that it is their responsibility to stand up against the blatant abuse of human dignity.”