(CNN) A couple in Utah told police they gave their newborn daughter a pain medication in the hospital to cover up the fact that the child was born addicted to drugs.

Colby Glen Wilde, 29, and Lacey Dawn Christenson, 26, both of Elk Ridge, gave their daughter Suboxone, a prescription pain medication used for pain management and addiction treatment, on the day she was born, according to a press release from the Utah County Sheriff's Office

Investigators learned that Christenson had been using heroin and prescription pain medication heavily during her pregnancy, leading to the child being born addicted to the drugs, the press release said.

The episode occurred April 9, the day the girl was born at Utah Valley Hospital, the sheriff's office said. The couple told authorities they crushed up Suboxone pills and put the powder on the infant's mouth and gums while medical staff were out of the room.

According to the press release, informants told law enforcement that parents of drug-addicted babies sometimes do this to hide signs of addiction from hospitals.

The couple were not arrested until June 26, when Wilde was taken into custody after an incident at a Walmart in Spanish Fork, Utah, where he was accused of stealing merchandise. Christenson was also in the store and arrested on an outstanding warrant.

Sheriff's deputies said that when store employees and bystanders tried to apprehend Wilde, he handed his infant daughter to a stranger, ran to his car and began driving away.

With the parents in jail, the couple's three other children -- all boys, ages 2, 4 and 8 -- were taken into custody by the Utah Division of Child and Family Services. Their now 3-month-old daughter was evaluated at the hospital, and the other children were also drug tested. On June 28, deputies also got a search warrant for the home based upon a tip from someone caring for the couple's pets while Wilde and Christenson were in jail.

"Deputies discovered items of drug paraphernalia in many different areas of the home, including next to a baby bassinet, next to a child's sippy cup, and others," said the press release. As a result, additional charges were filed against the couple.

The couple were released from jail on the prior charges -- Christenson on June 28, Wilde on July 5 -- but deputies served a second search warrant on July 18 because they had information that the parents were still doing drugs. When deputies arrived to do the second search warrant, they found Wilde "actively smoking heroin," Sgt. Spencer Cannon, public information officer for the Utah County Sheriff's Office, told CNN.

Christenson and Wilde were charged with distribution of a controlled substance in a drug-free zone, use of heroin and methamphetamine, endangerment of a child and possession of drug paraphernalia. Cash bail for the pair was set at $10,000. It wasn't clear Monday if either one of them had an attorney.

Deputies later learned the results of the children's drug tests.

"The oldest child did not test positive for any drugs," Cannon said. But the three younger ones all tested positive for methamphetamines, while the infant also tested positive for heroin and morphine. Cannon said Christenson was given morphine for pain during the delivery and that was the source of it in the infant.

To test the children for drugs, authorities tested their hair follicles, Cannon said, adding that "evidence of drugs in the body remains in the hair for longer than it would in blood or other means of testing."

Police said they don't believe the other children were given drugs directly like their infant sibling but that their parents smoked drugs in their presence and the kids ingested the smoke secondhand.

"They were routinely exposed to secondhand smoke from (the parents') smoking methamphetamines and heroin," Cannon said.

Authorities said that despite the secondhand exposure, the children weren't exhibiting any signs of ongoing problems from the drugs.

After the execution of the second search warrant, the couple admitted to investigators that the crushed pills found in their home was the Suboxone used on the daughter in the hospital, Cannon said. Christenson and Wilde told authorities they talked about it with their friends and came up with the plan together.