Peru has cleared the government of ex-President Alberto Fujimori of carrying out a campaign of forced sterilisations in the 1990s.
Prosecutors say they found no evidence to support claims that hundreds of mostly poor and indigenous women and men were sterilised against their will.
The Fujimori government has always maintained all operations were consensual.
But human rights groups have reacted angrily, saying they will appeal.
An independent congressional commission established in 2002 that the government of Alberto Fujimori had sterilised 346,219 women and 24,535 men during his terms in office between 1990 and 2000.
It was part of a voluntary programme to reduce the country’s birth rate and, it was argued, help parents lift their families out of poverty.
The campaign had the backing of international donors including the United Nations Population Fund, Japan and the United States, as well as anti-abortion and feminist organisations alike.
Peruvian President Alberto Fujimori speaks in Lima, Peru, on June 6, 2000 The government of Alberto Fujimori has always maintained all sterilisations were consensual
But hundreds of people, some of them illiterate, said they were forced to undergo operations and not told they could have refused.
‘Serious violation of human rights’
After interviewing many of the alleged victims, Public prosecutor Marco Guzman, however, concluded that no crimes had been committed, and decided to close the case.
He said he did not think the campaign was a criminal strategy orchestrated by the Fujimori government.
“The women would come to the clinic, agree to the procedure, and undergo sterilisation. That was the regular, normal process,” he concluded.
The investigation was reopened in 2011 after being archived two years earlier.
It could have extended the 25-year jail sentence of Mr Fujimori, whose convictions for human rights abuses relate to Peru’s internal conflict, not his birth-control campaign.
A Peruvian feminist organisation, Demus, condemned the decision, saying in a statement: “The programme was a public policy that promoted the sterilisation of thousands of women in the country, especially in rural areas, who by deception and blackmail were deprived of their reproductive capacities.”