PHOENIX (AP) — A lawyer wounded by a gunman in a Phoenix office shooting this week has died, the second of three people hit by gunfire in the attack, the publicist for his law firm said Friday.

Mark Hummels, 43, had been on life support at a Phoenix hospital after Wednesday morning's shooting that killed a company's chief executive and left a woman with non-life threatening injuries.

Colleagues of Hummels described him as a smart, competent and decent man who was a rising star in his profession and dedicated to his wife, 9-year-old daughter and 7-year-old son.

The gunman — Arthur Douglas Harmon, 70 — was found dead early Thursday in the Phoenix suburb of Mesa from an apparent self-inflicted gunshot wound, police said.

Harmon opened fire at the end of a mediation session at a north-central Phoenix office building over a lawsuit he filed last April.

Steve Singer, 48, a father of two and CEO of Scottsdale-based Fusion Contact Centers LLC, died hours after the shooting.

Harmon targeted Singer and Hummels and "it was not a random shooting," police said. A 32-year-old woman not involved in the mediation was caught in the gunfire near the building entrance and suffered a gunshot wound to her left hand.

Fusion had hired Harmon to refurbish office cubicles at two call centers in California.

Hummels worked with the Phoenix law firm Osborn Maledon and focused on business disputes, real estate litigation and malpractice defense. He died Thursday night, publicist Athia Hardt told The Associated Press early Friday.

He was a reporter for the Albuquerque Journal and Santa Fe New Mexican before he left to go to law school in 2001. He graduated first in his class at the University of Arizona's law school.

Hummels was admitted to the Arizona bar in 2005.

"This is a day of just unspeakable sorrow," said 9th U.S. Circuit Court of Appeals Judge Andrew Hurwitz, who hired Hummels straight out of law school to serve as a law clerk from 2004 to 2005 while Hurwitz was serving on the Arizona Supreme Court.

According to court documents, Harmon was scheduled to go to a law office in the building where the shooting took place for a settlement conference.

Harmon represented himself in the lawsuit, and Hummels represented Fusion.

Fusion said Harmon was paid nearly $30,000 under the $47,000 contract. But the company asked him to repay much of the money when it discovered the cubicles could not be refurbished, according to the documents.

Harmon argued Fusion hung him out to dry by telling him to remove and store 206 "worthless" work stations after the mix-up was discovered. Harmon said Fusion then told him that the company decided to use a competitor.

Harmon's lawsuit had sought payment for the remainder of the contract, $20,000 in damages and reimbursement for storage fees and legal costs.

The company countersued Harmon, protesting the sale of his home to his son for $26,000 and asking a judge to prevent Harmon from getting rid of other assets. Harmon said the company's claims that the home was fraudulently transferred to his son were unfounded.