The Trump administration’s decision last year to abruptly dissolve the U.S. Agency for International Development — once the world’s leading aid donor — has been followed by a significant and sustained increase in violence across several African countries that the agency had supported, according to a study published Thursday in the journal Science by researchers from universities in Europe and the United States.

The study found a correlation between the sudden termination of USAID programs and rising conflict in regions of Africa that had historically received the most American assistance. The researchers examined violence data following the administration’s elimination of more than 90% of foreign aid contracts, a move that effectively cut some $60 billion in funding and disrupted staffing, procurement, and program operations across the continent.

“The abrupt withdrawal of USAID led to a significant and sustained increase in conflict across Africa’s most USAID-dependent regions,” the study stated.

The authors were careful not to attribute the violence directly to the cuts. They described the findings as evidence that “large-scale, sudden aid cuts can destabilize fragile settings” — not that more aid inherently reduces conflict, but that the disruption itself carries destabilizing consequences.

Africa faces a greater threat from jihadi violence than any other region in the world, according to conflict experts. The Armed Conflict Location & Event Data project, or ACLED, reported Wednesday that jihadis on the continent have been more involved in violence across the board and have increasingly targeted civilians over the last four years.

For many years, USAID had served as the key funding partner for African governments and aid groups responding to multiple crises. In Nigeria, American assistance supported victims of the Boko Haram insurgency, which has raged since 2002. In Ethiopia’s Tigray region, officials had relied heavily on U.S. funds as full-scale recovery efforts remained stalled after a war that killed hundreds of thousands. In northern Ivory Coast, a front line in the global fight against extremism, USAID had made significant financial commitments to counter the spread of al-Qaida and Islamic State group affiliates.

Nathaniel Raymond, executive director of the Humanitarian Research Lab at the Yale School of Public Health, who was not involved in the study, said the damage extends beyond the loss of funding. “The lasting problem with the shuttering of USAID is likely going to be that for much of its conflict prevention work, even if you put back all the money … the experience is gone,” Raymond said.

Ladd Serwat, senior Africa analyst at ACLED, said some of the terminated USAID programs may have helped prevent spillover from conflict zones. “We now see increasing insurgency and spillover, so some of those programs may have supported these communities from insurgent threats, and now they are no longer active,” Serwat said.