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HUNTSVILLE (AP) — A Fort Worth man convicted of killing a father and his infant son in 1987 is set for execution Tuesday evening.

Sixty-one-year-old James Bigby fatally shot 26-year-old Michael Trekell and suffocated Trekell’s 4-month-old son Jayson on Christmas Eve 1987 at their Arlington home.

Within hours, evidence showed he also killed two other men, believing they along with Trekell were conspiring against him in a workers’ compensation case he filed against a former employer.

Bigby was never tried for those men’s killings.

At his trial in 1991, Bigby grabbed a loaded gun from behind the judge’s bench during a court recess and tried to abduct the judge.

Bigby would be the fourth inmate executed this year in Texas and the sixth nationally.

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