Some early clues have surfaced in the death investigation into what killed Foo Fighters drummer Taylor Hawkins ... investigators say tests show drugs were in his system.
In a release from the Attorney General's Office in Bogotá, Colombia, officials say a toxicology test taken from Hawkin's urine revealed 10 different substances -- including opioids, tricyclic antidepressants and benzodiazepines.
Investigators say they will continue to work on Hawkins' case ... but obviously, the drug test is telling.
As we reported, Hawkins -- who first found fame as the drummer for Alanis Morissette -- before joining Foo and even starting his own band, was found dead Friday in a hotel room.
A post from the Foo Fighters read, "The Foo Fighters family is devastated by the tragic and untimely loss of our beloved Taylor Hawkins. His musical spirit and infectious laughter will live on with all of us forever."
Hawkins, Dave Grohl and other members of the band were in Colombia for several shows at the time of his death.
Taylor was open about his previous struggles with substance abuse, surviving a heroin OD back in 2001.
He was 50.