Rick Warren: Son used unregistered gun in suicide

TUSTIN, Calif. Pastor Rick Warren has tweeted that his son killed himself with an unregistered gun purchased through the Internet.

Warren, who has been tweeting regularly about his grief since his 27-year-old son Matthew committed suicide last Friday, said he forgives whoever sold the weapon.

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Orange County Sheriff's spokesman Jim Amormino said Thursday that the gun's serial number was scratched off.

It's illegal in California to buy a gun without a background check and purchasers are supposed to register their firearms. Defacing a gun's serial number is a federal offense.

Rick Warren is pastor of Saddleback Church in Orange County and author of "The Purpose-Driven Life," a bestseller. He and his wife have said their son struggled with depression. They have set up a mental health fund in Matthew's memory.