It has become a Saturday morning ritual since rebels seized the Congolese city of Goma: Residents come out of their homes, report to militia authorities and, at gunpoint, scour the streets, unclog the sewers, scrub the food markets and disinfect the morgues.

Those who show up late or skip compulsory work gangs risk heavy fines, public whippings or arrest.

Such is life in occupied Goma, home to two million people in eastern Democratic Republic of Congo, since M23 rebels, reinforced by thousands of troops from neighboring Rwanda, seized power in a lightning offensive in January, according to residents interviewed by The Wall Street Journal.

The traces of Congo’s central government—police, urban administrators, magistrates—have disappeared, replaced by the heavy-handed, sometimes violently enforced, rules of a rebel movement that after years in the bush suddenly finds itself in charge.

Jean Malenga, a motorcycle taxi driver, was returning to Goma late last month when he ran into a rebel checkpoint. He pleaded with the militiaman that he had missed mandatory cleanup because he had been away.

A M23 rebel stands guard at the the Unite stadium as members of the armed forces of the Democratic Republic of the Congo (FARDC) and Wazalendo troops wait to be taken aboard trucks for training by M23 rebels, in Goma, North Kivu, Democratic Republic of Congo, May 10, 2025. REUTERS/Arlette Bashizi

The rebel fighters slapped him across the face, Malenga said. The 30-year-old said he won’t risk missing another shift for fear of being beaten or detained.

Human Rights Watch, the watchdog group, has accused the rebels of executing people suspected of having links to the Congolese army, which has been vanquished in Goma and other parts of eastern Congo. In February, rebels killed a popular musician, Delcat Idengo, as he filmed a music video critical of the conflict in Goma.

“They now know my address—I have nowhere to hide,” said Malenga, the taxi driver. “We have to accept the new way of life.”

Residents say it is almost impossible to move around the city, a key trading hub for minerals, without confronting armed rebels eager to exercise their newfound authority. At checkpoints, M23 rebels screen men and boys for conscription, sometimes checking the contents of mobile phones and extorting money, according to residents. Rebel-appointed neighborhood captains encourage locals to report government sympathizers.

Some rebel commanders impose fines totaling about $35 on those who fail to show up for cleanup crews, a substantial sum in a country where, according to the World Bank, three out of four people live on about $2.15 a day.

The crackdown on civilians is reminiscent of the strict demands imposed on residents of Rwanda’s capital, where monthly compulsory cleanups have turned Kigali into one of Africa’s cleanest cities.

Perhaps it isn’t a coincidence.

Like the M23 rebels, the Rwandan government is led by members of the Tutsi ethnic group. In Rwanda, the Tutsis suffered hundreds of thousands of deaths during the 1994 genocide at the hands of their Hutu rivals. The Tutsis fought back 30 years ago and, under President Paul Kagame, have created a well-managed—if highly repressive—country.

In Congo, the M23 rebel group spent 13 years in the bush before this year’s battlefield victories brought it to power in much of eastern Congo.

Rwandan officials say they are compelled to protect their ethnic brethren from what they describe as Hutu extremists around Goma and eastern Congo. But Rwanda denies United Nations reports that it dispatched 4,000 special-forces troops to help the rebels break through defenses manned by Congolese soldiers as well as African and U.N. peacekeepers.

The Trump administration, which is negotiating with the Congolese government over access to valuable minerals , is trying to broker a truce between Rwanda and Congo, according to U.S. officials.

The rebels appear to be re-creating the Rwandan model in Goma. “There will be special administrative units in all areas under our control,” Corneille Nangaa, the M23 president, told a rally in Goma in February. “Our priority is to bring you peace.”

With around 9,000 fighters scattered across the swaths of mineral-rich territory, M23 has relied on forced labor and forced recruitment to solidify control, according to Clémentine de Montjoye, a senior researcher at Human Rights Watch.

During the group’s rapid advance, rebel fighters, for instance, abducted local activist Pierre Katema Byamungu and seven other men, forcing them to perform unpaid manual labor. They later shot and killed Byamungu and four of the others, accusing them of being members of a pro-government militia, according to Human Rights Watch.

“It has become a common practice throughout M23-held areas for people to be subjected to forced labor, sometimes to clean up the city or other times to build roads,” Montjoye said. “Those who refuse are subjected to beatings or forcibly taken for training.”

An M23 spokesman denied the allegations. Lawrence Kanyuka, a rebel spokesman, told a Goma radio station last month that the measures were needed to deal with the mess that Congolese authorities left behind when they fled.

“Goma is a lot cleaner now, but the rights abuses are appalling,” said Matthieu Muhima, a resident and coordinator from charity group CARE International.

The difficulty of safely moving between areas held by different armed groups has made it harder for charities to distribute lifesaving aid to the over one million people displaced by the conflict since January, according to aid agencies.

“Rwanda is directly responsible for this misery,” said Congolese Foreign Minister Thérèse Kayikwamba Wagner.

A Rwandan government spokesman didn’t respond to a request for comment.

Meanwhile, the region is slipping even further from Congolese control. Congo’s central bank closed down Goma bank branches and severed payments to municipal authorities. City employees, unable to access their accounts, have gone AWOL, leaving morgues, water-treatment plants and markets untended.

Aid officials and residents in need of cash have to make a circuitous 1,000-mile trip through Rwanda and Uganda to reach working banks in government-controlled areas, according to humanitarian officials.

Across rebel-held areas, local currency is in such short supply that some business owners are switching trade from Congolese francs to Rwandan francs, residents say.

“The conflict is tipping the eastern Congo into financial collapse, further eroding what little sovereignty remains of the Congolese state,” said Jervin Naidoo, an analyst with Oxford Economics Africa.

The rebels, who previously relied on forced labor to widen roads to accommodate trucks smuggling minerals into Rwanda, have now imposed a 15% levy on miners in areas under its control.

This month, Patrick Kagoma, who runs a motorcycle-repair shop in Goma, skipped a planned bus trip to Uganda so he wouldn’t miss the mandatory cleanup. Previously, Kagoma, 38, would pay around $60 for a bus ticket to Kampala to procure supplies for his shop. But owing to the numerous rebel checkpoints and tax-collection centers, his expenses have more than doubled.

“Rebel tax collectors are very strict,” he said.

The U.N. says M23 collects around $800,000 a month from coltan—a mineral used in smartphones and laptops—at mines it controls, but rebel commanders are pressing miners for more. Twangiza Mining, one of the largest gold miners in the region, this past week halted operations at its site south of Goma, citing new M23 tax demands.

The M23-appointed governor of South Kivu province, Birato Rwihimba Emmanuel, told Reuters the company had long evaded paying taxes and must now comply with the new rules. A Twangiza Mining spokesperson couldn’t be reached for comment.

Write to Nicholas Bariyo at nicholas.bariyo@wsj.com