Orange County, Calif., was rocked Tuesday morning by a shooting spree that left three people dead and a number of others wounded before the gunman killed himself with a shotgun as police drew near, authorities said.

The early-morning shooting spree came about a week after ex-LAPD officer Christopher Dorner -- who was being hunted on suspicion of a series of four murders --- died at the conclusion of an extensive manhunt that stretched across much of Southern California.

The Tuesday shooting spree seems to have started early that morning in a Ladera Ranch home, where the gunman is believed to have shot a woman to death,  Orange County Sheriff's Department spokesman Jim Amormino said, according to the Los Angeles Times, which added that 911 fielded a call from an address there at 4:45 a.m. Upon responding to the call, deputies found the victim dead in the home.

Reuters reports that authorities are still trying to figure out what, if any, relationship existed between the suspect and his first victim. It is believed that he did not know any of his subsequent victims.

After the first killing, the man fled in an SUV and drove to Tustin, where police say he carjacked someone around 5:30 a.m. near the I-5 Freeway, the L.A. Times reported. The suspect then shot and wounded a bystander who is expected to survive, Amarmino said, according to Reuters.

Minutes later, the suspect allegedly committed another carjacking, this time against a man driving a BMW, Reuters reported.

"He orders him out of the vehicle, walks him to the side of the curb and then executes our victim," Santa Ana police Cpl. Anthony Betagna told Reuters.

Another carjacking was undertaken near a Tustin computer store shortly thereafter, during which one person was shot to death and another was shot but was transported to a nearby hospital, the L.A. Times reported. The suspect was stopped by law enforcement officers soon after in a stolen vehicle in the city of Orange, and immediately proceeded to kill himself with a shotgun, Reuters reported.

The motive is unknown at this time, according to the L.A. Times, and the investigation continues.

"We're still investigating how many victims we might have," Garaven told Reuters.