A teenager was arrested Saturday night and charged with the murder of a 23-year-old nursing student.

Kimothy Simmons, 17, is suspected in last week's slaying of Sarah Whitlock.

Investigators have said that Whitlock was stabbed to death in her Riverside apartment on March 10 by Simmons, who may have been impersonating a police officer at the time.

Authorities said Simmons was arrested during a carjacking and brought in for questioning. His arrest came on the same day that Whitlock's ashes were scattered at sea.

Undersheriff Frank Mackesy said a detective remembered seeing Simmons on a surveillance tape that showed him allegedly shoplifting a shirt with the word "police" on it.

On the night Whitlock was killed, police said they found a narcotics officer's baseball cap, and a price tag from the police T-shirt, plus an unloaded gun and holster.

Investigators said Simmons admitted to stealing all of the items, but has not confessed to killing Whitlock.

"Since our broadcast last Thursday of our concerns about the possible impersonation of a police officer ... we have received multiple leads," Mackesy said. "Although this was a senseless act of violence, we have reason to believe this was not a random act."

Mackesy said Simmons targeted Whitlock after meeting her at the Jacksonville Landing, where he allegedly told her that he was a "police recruit."

After Whitlock's slaying, police told residents to closely examine officers' identification before letting them into their home. Simmons' mother, Roxanne Washington, said the teen told her he didn't kill Whitlock. "I don't believe he did it, but if he did, I do feel sorry for (Whitlock's family). My heart goes out to them. I know sorry can't change it and turn it around, but I'm truly sorry if he did," Washington said.

According to police, Simmons was locked up in a juvenile detention center at age 12 for reasons unknown, and was later arrested for escaping from the facility. At 14, Simmons was arrested for carjacking, and at age 15 arrested again for car theft.

Simmons was expected to appear in front of a juvenile judge Monday morning, but waived his appearance. He is being held without bond.

"The state attorney now, will make a decision on how they're going to charge him, and when they're going to charge him, and whether they're going to charge him as an adult, which they can do," said Simmons' attorney Bill White.

Simmons' next scheduled court date is for March 30.

Previous Stories:

• March 20, 2006: Police: Arrest Made In Stabbing Of Jacksonville Student
• March 17, 2006: JSO Warns Citizens To Ask Officers For Proper ID
• March 14, 2006: Police: Riverside Woman Wasn't Sick, She Was Killed