Peru's government has formally lodged a request for the extradition of former president Alberto Fujimori from Chile.
Mr Fujimori denies any wrongdoing
If extradited, Mr Fujimori faces prosecution on 12 charges from corruption to human rights abuses.
Mr Fujimori - president between 1990 and 2000 - fled to Japan after his government was mired in a corruption scandal. He denies wrongdoing.
He was detained in Chile after arriving unexpectedly in November, vowing to launch a political comeback.
The extradition request files - which one report says filled 12 boxes - were delivered to Chile's Foreign Minister Ignacio Walker by Peru's ambassador to Chile, Jose Antonio Meir, and special prosecutor Antonio Maldonado on Tuesday morning.
According to the Chilean newspaper La Tercera, the papers will now be passed on to Supreme Court Judge Orlando Alvarez to assess the application.
The 12 charges compiled by Peru against Mr Fujimori include using a death squad to kill 25 people in two incidents known as La Cantuta and Barrios Altos, illegal phone tapping, bribery and the payment of more than $15m to Mr Fujimori's spy chief, Vladimiro Montesinos.
Mr Fujimori - who has dual Peruvian-Japanese citizenship - arrived in Chile on 7 November hoping to launch a bid for the Peruvian presidency in 2006, despite being barred from public office until 2011.
Instead he was detained on Peru's request. Japan had refused repeated extradition requests.
Mr Fujimori, who says the charges against him are politically motivated, is a divisive figure in Peruvian society.
To some, he was the saviour of a country on the verge of economic collapse and racked by political violence. To others, he was a corrupt, authoritarian strongman who rode roughshod over the country's democratic institutions.
Opinion polls suggest the bulk of Peruvians oppose any electoral return for the former president, but up to a fifth of the population would consider supporting him or a candidate with his backing.