CUPERTINO (CBS / AP) — The family of the man who shot and killed three colleagues at a Silicon Valley cement plant and wounded six others says they are shocked and have no explanation for why the shooting happened.

Cupertino gunman suspect, workplace shooting, Shareef Allman

Shareef Allman (Cupertino PD)

In a statement released Saturday, Shareef Allman’s family members call the incident a “horrific tragedy” and express their condolences to the victims and their families.

They say the Allman they knew was a loving father and good man.

Allman was shot dead by sheriff’s deputies Thursday morning, a day after the shooting at Lehigh Southwest Cement plant, where he worked as a truck driver.

Authorities have not released any details about a possible motive, other than to say that Allman was disgruntled.

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