ROYAL OAK (WWJ) – Twenty years ago Monday, a disgruntled postal employee burst into the Royal Oak Post office, killing four people, injuring four others and then taking his own life.

Clark French was a letter carrier in 1991. He was shot by 31-year-old Thomas McIlvane.

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“The bullet went through my liver, gall bladder and colon,” French said. “So, I guess … it went in my right side, maybe halfway up my right side.”

Fired for insubordination, McIlvane held his 22-caliber rifle and shot 100 rounds. He hit French, who fled outside into the chaos. It took French a year- and-a-half to physically recover — mentally much longer, something he says is a daily process.

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“There’s something that hasn’t occurred to me in a long time that used to occur to me daily after the shooting. It’s things like that. It’s hard to explain, but there is a healing process that is still continuing.

French no longer works for the U.S. Postal Service. He switched careers entirely, and is now an engineer.

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A tree was planted at the Royal Oak Post Office in honor of everyone affected by the shooting. A simple observance of the anniversary will take place shortly before 9am — when the shooting actually occurred.