Amber Alert: 7-Year-Old Aja Johnson Believed to Be With Accused Murderer

7-year-old Aja Johnson's behavior will become "unruly" without her medication.

Jan. 26, 2010 — -- A 7-year-old Oklahoma girl who needs medicine for a psychological condition is believed to have been kidnapped by a man prosecutors charged today with the murder of the girl's mother this weekend, officials said today.

Comanche County prosecutors charged Lester Hobbs, 46, with first-degree murder in the beating death of his estranged wife Tonya Hobbs, whose body was found Sunday in her camper. They also charged Hobbs with kidnapping of Aja Johnson, who is not his biological child.

Aja's abduction is believed to have occurred sometime before 9 p.m. Sunday, when her mother's body was found by authorities at the Comanche County Sheriff's Office.

Tonya Hobbs' murder comes just five months after she filed for a protective order against her estranged husband who she said threatened to kill her if she ever left him. While an Oklahoma court initially granted the request, the case was later dismissed because neither Tonya Hobbs or Lester Hobbs showed up in court.

Earlier today, attorney John Branch, who is representing Aja Johnson's father, J.J. Johnson, told that without her medication the young girl's behavior will become erratic. Aja suffers from attention deficit disorder and sleep deprivation, said Branch, and without her medicine is likely to misbehave.

In a press conference today, Aja's father made a tearful plea for her safe return and reiterated his daughter's need for medical treatment.

"I'm here to make a plea to everybody who's listening. I need my little girl back," Johnson said. "She's missing, and I love her dearly. She needs her medication."

Authorities and Aja's family are worried the young girl could be in danger because of Hobbs' violence history.

According to public records, Hobbs has been in and out of prison for various charges, ranging from a conviction for burglary in 1983 to driving under the influence. Most recently Hobbs servied a 20-month prison sentence in 2005 for assault and battery with a deadly weapon.

Aja and her mother were visiting Hobbs at his sister's home prior to the murder and disappearance, according to authorities. Also traveling with Aja and her mother was Aja's older sister, who is not missing.

Amber Alert for Aja Johnson

Johnson had had custody of Aja since November 2009, according to Branch, and last saw his daughter Friday evening.

Aja, described as a 65-pound, 4-foot tall girl with brown eyes and brown hair, was last seen Saturday evening at her Geronimo, Okla., home.

"She's only been 7 years old for 20 days," said Aja's father before breaking down.

Calls made to Comanche County Sheriff Kenny Stradley for comment regarding the case were not immediately returned, but a statement about the death of Tonya Hobbs was released by the Oklahoma State Bureau of Investigations, which is helping with the investigation.

"Investigators do believe she was murdered," the statement said.

The cause of death is not yet known, according to the OSBI. The medical examiner's office is performing an autopsy on the body.

Hobbs is believed to be driving a white 1992 Toyota Paseo with Oklahoma license plates that read 577-BPW. The back window of the two-door car has been replaced with a piece of sheet metal, according to The National Center for Missing & Exploited Children, and the vehicle has no hubcaps.

Anyone with information about Aja is asked to contact the Comanche County Sheriff's Office at 580-353-4280.

The Associated Press contributed to this report.