Arthur Douglas Harmon case: Man accused of shooting Steve Singer, Mark Hummels, Nichole Hampton

PHOENIX - A man suspected of shooting three people at a Valley law firm remains on the loose as of Thursday morning, and is considered "armed and dangerous".

Authorities on Wednesday afternoon identified the shooting suspect as 70-year-old Arthur Douglas Harmon.

Harmon is believed to have fled the shooting scene at 16th Street and Glendale Avenue in a rental car. The vehicle is described as a white 2013 Kia Optima, with Arizona license plate AVS-2052, according to Sgt. Tommy Thompson.

SWAT officers were unable to locate Harmon at his home near 28th Street and Acoma Drive in north Phoenix. Officers and two armored vehicles could be seen outside the home as SWAT officers made their way inside.

Sgt. Steve Martos said police outside the home were interviewing the 70-year-old's wife and son.

Police said Harmon's son initially refused to let police into the home, so they had to wait outside for a search warrant.

Authorities said they removed several items from Harmon's home, but would not elaborate on what they found.

A homeowner who lives nearby told ABC15 Harmon's cell phone was found in the front yard of a home about three miles away from where Harmon lives.

An exclusive Google Street View photo showed us the first glimpse at Harmon, seen gardening outside his house. It is unclear when the image was captured.

Authorities have been searching for Harmon since Wednesday morning when he allegedly opened fire at a Phoenix office complex.

Harmon is currently involved in a lawsuit with another person living at the north Phoenix home. It is believed the shooting happened after a scheduled mediation regarding the lawsuit.

Police confirmed 48-year-old Steve Singer was killed in the attack. Mark Hummels, 43, remains in critical condition, and a 32-year-old Nichole Hampton was shot in the hand and is expected to make a full recovery.