Ex-soccer star Sergio Contreras -- aka Koke -- was arrested in Spain on Tuesday as part of a massive drug raid ... and cops say they recovered a TON of hashish.
Literally, a metric TON.
36-year-old Contreras is pretty famous in Europe -- he made a fortune playing for big teams like the Ligue 1 club Olympique de Marseille and the famous Greek team Aris Thessaloniki.
But, ever since his pro career ended in 2016, cops say he's been RUNNING a major drug ring out of Southern Spain.
On Tuesday, cops launched a multi-city raid .