Detectives have not confirmed that Valdivia was with Martinez, but are searching for him because the girl ran away from her family's Clearfield home with him about four months ago, Keller said.
The two "apparently considered themselves boyfriend and girlfriend," said Clearfield Assistant Police Chief Mike Stenquist. Martinez was a friend of the girl's mother and had been living with the Valdivia family at the time, he said.
Other family members did not tell police about the girl's connection to Martinez until a week after she went missing, he said. They were found in Sacramento on Oct. 5.
"When we interviewed her after, she wouldn't disclose any information. She wouldn't talk to us," Stenquist said. Martinez was charged with child kidnapping. He has entered a not guilty plea. "We had a good case even though she was not going to testify or cooperate," he said.
When Valdivia disappeared again last week, she was living in a foster care facility in South Salt Lake and wearing an ankle monitor, which she disabled and removed, Keller said.
Police in Washington state did not know about Valdivia's missing person report when two deputies tried to talk to Martinez in a Walmart parking lot in Port Orchard, Wash., on Sunday, Hedstrom said.
Martinez started running and the deputies gave chase.
"For reasons not yet known, the suspect turned and fired multiple shots," Kitsap County sheriff's spokesman Scott Wilson said.
Both officers were hit and unable to return fire, but a female officer arriving on the scene shot and killed the gunman, Wilson said. It's not yet clear who shot the female, believed to be in her teens, who died later at a Tacoma hospital. Ballistics tests on the bullets could show whether it was the deputy or Martinez, the state patrol said.
"We believe that she and the deceased gunman knew each other, that they were together," Wilson told the Associated Press. He said investigators don't know yet the relationship between the two.
Destany Droge, 22, of Bremerton, Wash., said the two people killed appeared to be a couple.
"As soon as she saw him get shot, she ran for him," she told The News Tribune of Tacoma. "She put herself in the line of fire."
Tacoma police said the deputies were both shot in the torso and were in satisfactory condition. They are expected to survive
"I've seen just the one deputy, he's in one of the rooms talking with family and co-workers," said Mark Fulghum of the Tacoma police. "Both of the deputies are going to be fine. They're going to be kept overnight for observation."
Autopsies were scheduled Monday for the two people killed.
A blue minivan that apparently belonged to the suspect has been impounded and will be searched for possible evidence, Hedstrom said.
The female deputy involved in the shooting has been placed on administrative assignment until the investigation is completed, which is standard practice.
Shoppers raced to take cover as the incident unfolded.
The officers were about 30 to 40 feet behind the suspect when he started firing, Ray Bourge told KOMO-TV. "Five or six shots were fired. ... I just went and took cover," he said.
Victor Meyers told the station that he heard the first shot, then six more in rapid succession.
"I heard one shot, which I thought was a car backfiring, and then several more reported back, which I knew to be gunfire," Meyers said.
He said he saw a female deputy running toward a victim on the ground before he and other witnesses were hustled from the scene.
The store was immediately locked down. Customers in the store were allowed to leave after investigators questioned them. The store reopened Sunday night, Hedstrom said, and the shooting scene was cleared.
Port Orchard is the county seat and has about 8,250 residents. The last time a Kitsap County sheriff's deputy was shot in the line of duty was in April 1978, according to The Tacoma News Tribune. Deputy Dennis Allred stopped to help what he believed to be a stranded driver towing another vehicle. The vehicle turned out to be stolen, and Allred was shot and killed by the suspects.
Martinez, a former Utah County resident, has a criminal record dating back to 1999, according to state court records.
Except for a felony drug possession charge that in 2006 landed him in prison for 16 months, his convictions are all misdemeanors.
In 1999, when Martinez was 18, he was charged in Provo's 4th District Court with second-degree felony theft by receiving. He entered a no contest plea in abeyance and the case was dismissed two years later.
In 2000, Martinez was charged in 4th District Court with damaging/interrupting a communication device, a class B misdemeanor. He resolved the case with a diversion agreement that included a $50 court fee and 15 hours of community service.
In 2001, he was convicted during a 4th District Court bench trial of class B misdemeanor retail theft. He was sentenced to 10 days in jail, which included eight days of work diversion, and fined $300. The same year, he was fined $100 after pleading guilty to a class B misdemeanor count of being in a park after curfew.
In 2002, Martinez pleaded no contest to class B misdemeanor criminal trespass in Springville's justice court and was fined $555.
Also in 2002, he was charged with third-degree felony aggravated assault for an incident in Orem. He pleaded no contest to a lesser count of class A misdemeanor assault and was sentenced to 90 days in jail, fined $580 and ordered to complete an anger management class. Two years alter, Martinez was accused of violating his probation and eventually was ordered to serve a year in jail.
Last year in Ogden's justice court, Martinez, who was then a resident of Roy, was charged with class B misdemeanor counts of disorderly conduct and domestic violence in the presence of a child. He resolved the case in December by pleading no contest to disorderly conduct, an infraction, and the other charged was dismissed. His sentence was a fine of $150.
Martinez, who was charged in October child kidnapping, was to appear in Farmington's 2nd District Court on Wednesday for a pre-trial conference. No trial dates had been set.
The Associated Press contributed to this report.