A Tucson man was killed early Saturday when a speeding car being followed by a police car ran a red light on East Speedway at North Alvernon Way, smashed into the man's 2002 Nissan Xterra and upended it, sending it crashing into another car, police said.

Roger A. Krause, 58, who was driving north on Alvernon, was coming home from his night shift at Texas Instruments, said police. Police said he was killed immediately, but it took three hours to remove his body from the crushed SUV.

The busy intersection was closed for more than six hours after the 6:10 a.m. crash, partly because of special investigative procedures used when police are involved before a crash, said Sgt Mark Robinson, Tucson Police Department spokesman.

Immanuel Samora, 22, the driver of the 1996 Toyota Paseo that struck the Xterra broadside, was injured in the crash and taken to the hospital where he underwent surgery for "severe injuries," Robinson said. Charges against Samora are pending his recovery.

Police are investigating whether speed and drug or alcohol impairment contributed to the crash, said Detective Sgt. Tim Beam, who supervises TPD's traffic investigations unit. Beam said alcohol or drugs are suspected because of statements made by Samora at the scene and the observation of him by paramedics.

Robinson said a board of inquiry was convened to determine whether police procedures were followed properly in the minutes before the crash.

According to Robinson, the speeding car was first spotted by an off-duty Tucson police officer, who was stopped in a marked patrol car in an eastbound lane on Speedway, waiting for the light to change at North Campbell Avenue.

The Paseo sped past the stopped patrol car, running the red light at Campbell. The officer switched on his emergency signals to get through the intersection and then turned them off.

Robinson declined to identify the officer, saying he was a veteran of at least 20 years, returning his car from an overnight off-duty job that required use of his patrol car.

When the Paseo slowed for traffic, the officer got close enough to read its license plate, then put his emergency signals on to make a traffic stop. He backed off when the Paseo sped up again, and witnesses to the crash told police that the squad car was not visible when the crash occurred, Robinson said.

The driver of the car struck by the Xterra, who was stopped in the westbound lane of Speedway when the crash happened, was not injured, Beam said.

Beam said he suspects the Paseo was traveling more than 60 mph based on statements from witnesses and "the dynamics" of the crash.