PHOENIX -- A gunman opened fire at an office complex here on Wednesday, wounding at least five people, one of them seriously, before fleeing, the police said. Several hours after the shooting, members of a police S.W.A.T. unit continued to check the building, but the whereabouts of the gunman were not known.
The extent of the victims' injuries was not immediately clear, but the police said one person was in critical condition. Four other people were hit by bullets, but did not suffer life-threatening injuries, and two others were taken to the hospital for stress-related symptoms.
Sgt. Tommy Thompson, a Phoenix Police Department spokesman, said witnesses saw the gunman talking to two people in the parking lot of the complex on Wednesday morning before he began shooting.
"We believe this was not random," Sergeant Thompson said. "We believe he came here for a reason."
Don Jacksa, a software engineer who works at the office complex, in north-central Phoenix, said that he heard unusual noises at about 11:30 a.m., but did not think much about them until one of his co-workers said the sounds had been gunfire. The co-worker locked the office door and they huddled inside until the police arrived, he said.
Mr. Jacksa said he thought that at least 100 people had been evacuated from the office complex.
Jeremiah Barnes, another worker in the complex, which is near Glendale Avenue and Arizona State Route 51, said that moments after he heard a gunshot he saw a man driving a white Infiniti, speeding recklessly in reverse out of the parking lot and nearly striking other vehicles.
His description of the vehicle matched that of other witnesses.
The shooting occurred hours after Gabrielle Giffords, a former member of Congress who was wounded in a shooting in Tucson in 2011, addressed the Senate Judiciary Committee, pleading for reform of the nation's gun laws. "We must do something," she said. "It will be hard. But the time to act is now."
Rebekah Zemansky reported from Phoenix and Timothy Williams from New York. Jennifer Steinhauer contributed reporting from Washington.
This article originally appeared in The New York Times.