'El Chapo': Mexico starts drug kingpin's extradition process to US
Mexico has formally started the process of extradition to the US of drug kingpin Joaquin "El Chapo" Guzman.
The authorities said Interpol officers served him papers at the Altiplano prison, near Mexico City.
Guzman, 58, escaped from the maximum security jail in July and was recaptured on Friday.
Mexico is also considering whether to investigate Hollywood actor Sean Penn, who interviewed Guzman soon after his jail break.
Unnamed Mexican officials have said Penn's secret meeting helped lead them to the fugitive.
In the Rolling Stone article, the result of a seven-hour meeting, Penn and Guzman discuss various topics, including drug trafficking.