South Carolina ? A man was executed Friday for killing four workers at a lawnmower parts plant in 1997 out of revenge for being fired from the factory.

Hastings Wise, 51, made no statement and did not look at the victims’ families, staring instead at the ceiling and taking deep breaths as a mix of chemicals went into his veins.

His chest stopped rising within about two minutes, and he was declared dead 10 minutes later.

Wise tried to die on the day of the killings by drinking insecticide after the plant emptied, but it only made him violently ill.

Prosecutors said Wise waited for the afternoon shift change at the R.E. Phelon plant in Aiken County so he could make sure all of his targets were there. He shot people who he thought led to his firing several weeks earlier or took jobs he wanted, authorities said.