Porsche-driving lawyer Nathan DeSai was Houston gunman

A "disgruntled" Porsche-driving lawyer wearing Nazi emblems has been named by police as the gunman who opened fire on a Texas street, injuring nine people.

Nathan DeSai, 46, began firing apparently indiscriminately at people driving by his apartment building in southwest Houston on Monday morning.

DeSai was killed during a shootout with police. Six people were shot and three had eye injuries from flying glass.

Police also recovered 2,600 rounds of live ammunition in his sports car.

A bomb squad search of the suspect's black Porsche convertible, which was parked at the scene, also found a semi-automatic rifle and a knife.

Officials said DeSai was wearing historic military attire with Nazi emblems and used a semi-automatic handgun during the attack.

Authorities also found a notebook with a Nazi symbol and recovered 75 shell casings at the scene.

The guns were purchased legally and the suspect had a licence to carry concealed weapons, police said.

Police say they are investigating the gunman's apartment and his social media accounts to try to establish a motive.

They found other historic military paraphernalia in his apartment, dating back to the US Civil War.

The city's mayor, Sylvester Turner, told reporters: "The motivation appears to be a lawyer whose relationship with his law firm went bad."

Prakash DeSai, the suspect's father, told an ABC Houston affiliate that his son was "upset about his law practice not going well" and financial problems.

DeSai graduated from University of Tulsa's law school in 1998.

He opened a small law firm with his former partner, Ken McDaniel, but the pair were forced to close it about six months ago, according to Mr McDaniel.