BERLIN (AP) — The Swiss government acknowledged Monday that authorities in the Alpine nation had failed to prevent the illegal adoptions of children from Sri Lanka up until the 1990s.

In a statement, the government said it regretted that such adoptions had gone ahead “despite strong indications of, in some cases, serious irregularities.”

The issue came to light several years ago after adults who had been adopted as children in the 1980s and 1990s returned to Sri Lanka to find their birth parents, only to discover that information contained in their files was sometimes false.

“Despite early and clear indications of illegal adoption placements in Sri Lanka, the (Swiss) Confederation and the cantons waited far too long before taking the appropriate action against the irregularities,” the Swiss government said.

“The negligence of the authorities has marked the lives of adults adopted as children to this day,” it said. “The Federal Council regrets that the Confederation and the cantons failed to shoulder their responsibility to the children.”

The government said it would provide greater support for adoptees searching for their origins and intended to launch a broader historical analysis of possible illegal adoptions in Switzerland.

Switzerland only recently acknowledged the suffering of Swiss children who were taken away mainly from poor families and single mothers, and were made to work on farms as late as the 1960s.