GOMA, Democratic Republic of Congo (Reuters) – Almost half of the 1.5 million people displaced by an insurrection in central Democratic Republic of Congo since last year have returned home as violence has waned in recent months, the United Nations said on Monday.

Fighting in central Congo’s Kasai region between government forces and militia fighters demanding their withdrawal from the region has killed up to 5,000 people since August of last year.

The violence in the usually peaceful center of the country has come amid concern over instability since President Joseph Kabila refused to step down at the end of his mandate last December.

The election commission said earlier this month that an election to replace Kabila, who came to power after his father’s assassination in 2001, will not be possible before April 2019 at the earliest – angering opposition members and raising the prospect of long-term unrest.

For now, the situation in Kasai appears to be improving.

The U.N. Office for the Coordination of Humanitarian Affairs (OCHA) said in a report that 710,000 people had returned to their homes in Kasai, while 762,000 remain displaced. Another 30,000 have fled to neighboring Angola.

It did not specify when those people returned home. But in a report on the humanitarian situation last month, it said 1.4 million remained displaced. It added that three million people are in a state of food insecurity in three of the Kasai region’s five provinces.

Congo’s government has devoted considerable resources to stamping out the insurrection by the Kamuina Nsapu militia, which began after Congolese forces killed a local chief who was an outspoken critic of Kabila.

Congolese forces’ heavy-handed tactics in suppressing the militia have drawn international condemnation.

The United Nations has accused both the government and the militia of carrying out summary executions, and the militia of using child soldiers. The sides both deny such charges.

Two U.N. investigators were killed in the region in March while investigating rights abuses.

While violence in Kasai has waned, it has flared in other areas. Militia in eastern Congo’s borderlands with Burundi, Rwanda and Uganda have formed new alliances to challenge the central government.