Congo's Catholic church released a report this week claiming that 3,383 people have been killed in the Kasai region since October. The church, the only institution which has a presence across most of this gigantic and largely lawless country, said the brutal killings were perpetrated by the national army, Bana Mura, a militia aligned with the government, and Kamuina Nsapu, a cultish armed group loosely tied to the country's main opposition party.

The astonishingly high death toll elicited calls for independent investigations at the United Nations and in Western capitals, but the conflict in Kasai has not received international attention proportionate to its size. Part of the neglect stems from the region's remoteness. Congo is about the size of the entire United States east of the Mississippi, and roads are scarce. Kasai in particular is deeply impoverished, with most of the population relying on subsistence farming. The difficulty of getting there, coupled with the threat of violence, has kept most activists and journalists away.

It is unclear how the Catholic Church gathered the information for the report.

The scale of the conflict is widening rapidly, however. More than 1.3 million people have reportedly been displaced from their homes by the fighting, and U.N. investigators say they've discovered at least 42 mass graves and dozens of razed villages.

The Congolese government has rejected outright the possibility of an independent investigation, saying it would violate its sovereignty, though it has agreed to cooperate with a U.N.-led inquiry.

In a speech on Tuesday, the U.N.'s top human rights official, Zeid Ra'ad al-Hussein, outlined the findings of his investigators in gruesome detail.

“My team saw children as young as 2 whose limbs had been chopped off; many babies had machete wounds and severe burns,” he said. “One 2-month-old baby seen by my team had been hit by two bullets four hours after birth; the mother was also wounded. At least two pregnant women were sliced open and their fetuses mutilated.”

He attributed those crimes to Bana Mura, a militia fighting alongside the national army against Kamuina Nsapu, which has in turn committed similar atrocities, according to the church and U.N. reports. He also said that the Congolese government's investigation into the crimes was “insufficient.”

Wars and explosive ethnic rivalries have riven Congo for decades, reaching a peak in the 1990s and 2000s when conflict in neighboring Rwanda spilled across the border. Pockets of fighting persist in the country's northeast, near Rwanda, but south-central Kasai is the theater of the worst bloodshed. Congo's military is poorly trained and barely paid, and often links up with local militias.

The situation is exacerbated by president Joseph Kabila's delaying of national elections, which has been interpreted by critics as a refusal to relinquish power. Kasai is populated mostly by ethnic groups that have never held national power in Congo, and is a bastion of opposition to Kabila.

The European Union and United States slapped sanctions on an array of top Congolese government and army officials — seemingly almost everyone but Kabila himself. The sanctions were put in place because Western governments think that Kabila's government has orchestrated many of the national army's human rights violations, as well as unlawful arrests of Congolese activists and journalists. Numerous foreign journalists and activists have been kicked out of the country.

In March, two U.N. investigators were kidnapped and killed while on a fact-finding mission in Kasai. Michael Sharp, an American, and Zaida Catalan, who held both Chilean and Swedish citizenship, were looking into the existence of mass graves in particular. The Congolese government declared that Kamuina Nsapu was responsible for their deaths, but numerous activists, aid workers, and journalists who watched a recording of their execution — released by the government — have called that narrative into question. The U.N. Security Council, the only body that could authorize an independent criminal investigation into their deaths, has yet to take that step, and the Congolese government has dallied in its own investigation.

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