Chris Cornell's Death Ruled Suicide, Source Says 'No One' Knew Musician Was 'Going Through a Dark Period'

A source tells ET that Cornell 'was a great father' whose kids 'must be crushed.'

Chris Cornell's death has been ruled a suicide.

A spokesman for the Wayne County Medical Examiner’s Office tells ET that the Soundgarden and Audioslave frontman's autopsy is complete and the cause of death is suicide by hanging.

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Cornell's rep, Brian Bumbery, confirmed to ET on Thursday that Cornell died at age 52. Bumbery said that the musician's wife, Vicky Karayiannis, and family are shocked by the news and asking for privacy.

A source close to Cornell and his wife tells ET that Cornell was "going through a dark period in his life."

"It's so sad. Horrific actually. No one had any idea that Chris was going through a dark period in his life," the source says. "His wife Vicky is absolutely devastated. They were kindred spirits -- so in love."

"Chris was a great father," the source adds. "His children must be crushed."

RELATED: Val Kilmer Reminisces About Partying With Chris Cornell: 'All the Women Were Literally at His Feet Listening'

If you or someone you know needs help, please call the National Suicide Prevention Lifeline at 1-800-273-TALK (8255).

Reporting by Brendon Geoffrion and Jennifer Peros.

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