A Tucson-based truck driver was sentenced this week to 29 years in prison in the attempted murder of two of his bosses.

Zane James Hammond, 34, was a commercial truck driver who authorities say attempted to kill a company CEO and vice president after a workplace dispute, according to a release from the Maricopa County Attorney’s Office. Hammond pleaded guilty to both counts.

Authorities say Hammond drove to the company’s Phoenix headquarters after he had quit following a customer dispute. When he arrived, he headed to the CEO’s office with a shotgun and fired. The CEO was not hit after he flipped his desk to take cover.

Hammond then pointed the gun at the company’s vice president and while attempting to load another round, the vice president rushed him, tackled him, disarmed him and held in a chokehold until Phoenix Police arrived, according to the release.

Hammond was sentenced to 15 years on one count and 14 years on another, with credit for 653 days served already. He was remanded to a Department of Corrections facility that offered substance abuse and mental health treatment.