Paul Makonda, governor of Tanzania's largest city, Dar es Salaam, vowed this week to begin mass arrests of “homosexuals in our city,” starting on Monday.

"I have received reports that there are so many homosexuals in our city, and these homosexuals are advertising and selling their services on the internet," Makonda said in a video posted to YouTube this past Monday.

"Therefore, I am announcing this to every citizen of Dar es Salaam: If you know any gays ... report them to me,” he said in the clip, which was translated from Swahili by CNN. Makonda then distributed a phone number so citizens could report gay people.

An LGBTQ activist reached by phone in Dar Es Salaam, who spoke to NBC News on the condition of anonymity to protect his safety, said Makonda held a news conference Wednesday in which he announced he had received over 18,000 messages since the YouTube video was posted Monday from Tanzanians reporting 200 alleged homosexuals and sex workers in Dar Es Salaam.

Makonda also warned international organizations and other countries not to interfere, saying Tanzania has its own “norms.”

“He was proud of himself," the LGBTQ activist said of Makonda. "He said this shows how people hate" gays.

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Many gay people in the city have not slept since Monday, the activist said, adding that the fear of vigilantism is high.

"We know our community," he said. "Once the community starts something like that … they always taking action by their own."

Makonda is forming a 17-member committee, which starts next week, in order to carry out his anti-gay crackdown. The committee, according to the activist, will consist of police officers, psychologists, telecom regulators and film regulators. He said the committee will target suspected gay people through social media and other online forms of networking.

The Refugee Coalition of East Africa, a registered LGBTQ community organization in neighboring Kenya, called the committee "an anti-LGBTQI surveillance squad" and sent a message to sexual and gender minorities in Tanzania: "We understand your plight and we have lived through your fear. If you choose to flee to Kenya, please know that we are here for you and we highly encourage you to reach out to any of our member organizations for support."

Homosexuality is punishable in Tanzania by a prison sentence of 30 years to life, one of the harshest punishments in the world for same-sex intimacy, according to Human Rights Watch.

The LGBTQ activist said Makonda’s rise began shortly after he was elected to office in 2016. Makonda reportedly rounded up sex workers and gay men and performed “forced anal exams,” a debunked Victorian-era practice where doctors attempt to determine a person’s homosexuality. The United Nations, Amnesty International and Human Rights Watch say the practice can amount to torture.

“For now it is very difficult; everyone is afraid,” the activist said. “As I am talking to you, most LGBT organizations have been shut down.” The activist recounted a 2016 party hosted by a friend where the police raided and arrested 20 people. The police then performed forced anal examinations on them, which Human Rights Watch reports is the first documented instance of the practice’s use in Tanzania.

The Citizen, a Tanzanian newspaper, reported from the Wednesday press conference that Makonda framed the crackdown as an attempt to regulate sex workers, who he accuses of advertising their services on social media. He warned locals that they had until Monday to “make sure that they have deleted pornographic pictures from their phones, because I wouldn’t like to see a public figure arrested due to photos included in his or her phone.”

The activist said Makonda has framed the anti-gay campaign as “for Tanzania, because those gay issues are against our norms, against God, against both beliefs, Islam and Christianity.”

Tanzania has earned a reputation for homophobia, according to Neela Ghoshal, a senior LGBTQ rights researcher at Human Rights Watch, and Makonda is known for being one of the most outspoken homophobic officials in the country.

“He is notorious for having essentially kicked off an ongoing two-year crackdown on LGBTQ people in Tanzania, starting in 2016,” Ghoshal said. “There have been peaks and slower times in that crackdown, but it's been basically really bad.”

Ghoshal said that unlike Tanzania’s northern neighbors, Kenya and Uganda, Tanzania has few public and open LGBTQ figures who will speak their truth on television and in the media. Even in Uganda, whose president, Yoweri Museveni, in 2014 signed a law that increased the penalties for being gay, there are public figures who respond to homophobia in the media.

“It’s almost a chicken or egg environment," Ghoshal said. "It is so hostile that people do not come out, so people don’t have a basic understanding of the issue."

Tanzanians, she added, "just absorb the hate speech of religious leaders and politicians," because "there is no counter narrative."

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