A suburban Buffalo man has pleaded guilty to charges stemming from the shooting death of a co-worker who was involved in a lovers' triangle via the Internet.

Forty-eighty-year-old Thomas Montgomery of Cheektowaga pleaded guilty today to first-degree manslaughter in the killing of 22-year-old Brian Barrett of Lockport.

Barrett's body was found in his vehicle in the parking lot of the suburban Clarence company where both men worked.

Montgomery admitted to shooting Barrett three times last September. He and Barrett had been involved in an Internet relationship with a middle-aged West Virginia woman who was using her daughter's Web page information to pose as an 18-year-old.

Montgomery -- who was charged with murder in late November -- faces sentencing at the end of October.