The group held an approved demonstration against gender-based violence Sunday ahead of International Women's Day, but authorities say it was a front to promote homosexuality.
Home Affairs and Internal Security Minister Jack Mwiimbu told VOA on Wednesday that his government does not promote LGBTQ rights and has made its position known since it came into power almost two years ago.
He condemned the march organized by the Sistah Sistah Foundation, saying it was against Zambian values and the law.
"I wish to warn members of the public not to allow and to flout the law deliberately by taking advantage of the prevailing environment that allow for freedom of expression and assembly," Mwiimbu said.
Zambia Police Deputy Spokesperson Dan Mwale told VOA the protesters did not follow the permit regulations, which only allowed them to protest sexual and gender rights and not promote LGBTQ rights.
"Investigations have intensified. Meanwhile, police have instituted investigations into the programs and activities of Sistah Sistah Foundation," he said.
Sistah Sistah Foundation declined to comment but put out a statement on Twitter saying it is shocked that the march, which it says was meant to highlight sexual violence against women, has been turned into horrific waves of hatred in public discourse, especially online.
The group said the four activists were released on police bond Wednesday and will soon appear in court. Three have been charged with giving false information to a public officer and, if convicted, could face up to seven years in jail.
Group co-founder Mwangala Monde has also been charged with unlawful assembly, and if convicted, could face an additional jail term of six months.
The statement further says that sexual violence against women and girls has been normalized, resulting in many people not paying attention to it. Recent police reports indicate that more than 20,000 cases of gender-based violence were reported in the last quarter of 2022 alone, most of them involving women and girls.
The weekend march, attended by about 300 people, has sparked debate in Zambia, with most people accusing the Sistah Sistah march of promoting LGBTQ rights, and calling for the organization to be banned.
Others said it's about time Zambians were allowed to discuss such issues so that they can decide the way forward.
In a statement after the march, chief government spokesperson Chushi Kasanda condemned the event, which she says was aimed at promoting LGBTQ rights in Zambia.
Same-sex sexual activity is prohibited under the country's penal code, which criminalizes acts of "carnal knowledge against the order of nature" and "gross indecency."
In 2005, Zambia replaced a British colonial-era law that saw the punishment for same-sex sexual acts increase from up to 14 years in prison to 15 years to life.
About 53% of lesbian, gay, bisexual, transgender and intersex people in Zambia have suffered violence in their lifetimes and over 70% have experienced verbal harassment, according to the United Nations Human Rights Committee.