A lawyer wearing a military uniform with a Nazi emblem and armed with two guns and nearly 2,600 rounds of ammunition opened fire on random passers-by in Houston early Monday, injuring nine before he was killed by the police, the authorities said.

Six of the victims were taken to hospitals, one in critical condition and another in serious condition, the police said. Three others were treated at the scene.

At a news conference on Monday afternoon, Capt. Dwayne W. Ready of the Houston Police Department described a tense episode that began about 6:30 a.m. local time.

The first reports of gunfire began to trickle in when children were being driven to school, workers were setting off for their jobs and it was still dark on Law Street, where the shooting took place. The street is part of West University Place, an upscale area in southwest Houston.