The mother-in-law of Formula One boss Bernie Ecclestone has been freed from her kidnappers -- UNHARMED -- and without having to pay the $36 million ransom ... cops say.
According to local media outlets, Brazilian officials say a police operation went down over the weekend -- and 2 suspects were arrested ... after cops traced them to a house in a poor neighborhood near Sao Paulo.
Officials say they were able to trace the location of the phone calls when the suspects were making ransom calls.
Cops launched a rescue mission and freed 67-year-old Aparecida Schunck after 9 days in captivity.