Police officers leave an office building after a shooting at the building in Phoenix on Wednesday, Jan. 30, 2013. A gunman opened fire at the Phoenix office building, wounding three people, one of them critically, authorities said. AP Photo/Patrick Sison People watch a women being taken to a paramedic truck from an office building where a shooter opened fire in north central Phoenix on Wednesday, Jan. 30, 2013. AP Photo/The Arizona Republic, Michael Schennum SWAT police officers inspect the roof of an office building after a shooting at the building in Phoenix on Wednesday, Jan. 30, 2013. A woman is taken to a paramedic truck from an office building where a shooter opened fire in north central Phoenix on Wednesday, Jan. 30, 2013. PHOENIX (AP) - A gunman opened fire at a Phoenix office complex on Wednesday, killing one person, wounding two others and setting off a manhunt. Police warned the public that he was "armed and dangerous." Authorities identified the suspect as Arthur D. Harmon, who they said opened fire at the end of a mediation session. They identified a man who died hours after the Wednesday morning shooting as 48-year-old Steve Singer. Police say a 43-year-old man was listed in critical condition and a 32-year-old woman suffered non-life threatening injuries. We believe the two men were the targets. It was not a random shooting," said Sgt. Tommy Thompson, a Phoenix police spokesman. Thompson said authorities believe Harmon acted alone and fled the scene in a car after the 10:30 a.m. shooting. Police didn't immediately release the names of the wounded. But a Phoenix law firm, Osborn Maledon, said one of its lawyers, Mark Hummels, was among the wounded. The firm said he "was representing a client in a mediation" when he was shot. According to court documents, Harmon was scheduled to go to a law office in the same building where the shooting took place for a settlement conference in lawsuit he filed last April against Scottsdale-based Fusion Contact Centers LLC. The company had hired him to refurbish office cubicles at two call centers in California, but a contract dispute arose. Fusion said Harmon was paid nearly $30,000 under the $47,000 contract but asked him to repay much of the money when the company discovered that 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. Pro tempore Judge Ira Schwartz, who scheduled the meeting, did not immediately return an email seeking comment. A message left Wednesday at the home of Fusion chief executive Steve Singer also was not returned. Hummels was representing Fusion in the lawsuit. As police searched for the shooter, SWAT teams and two armored vehicles surrounded his house about 7 miles from the shooting scene. Police served a search warrant to enter the home. For a time, officers, believing the shooter might be inside, used a megaphone to ask him to surrender. The gunfire at the office complex prompted terrified workers to lock the doors to their offices and hide far from the windows. Sood said police evacuated the office about 30 minutes after she first heard the popping noises. Around 10:30 a.m., the gunman arrived at the office building and got into a dispute with someone, a conflict that escalated to the point where he drew a gun and shot three people, police spokesman Tommy Thompson said. Vanessa Brogan, who works in sales support at an insurance business in the three-story complex, said she heard a loud bang that she thought at first was from somebody working in or near the building.