A Hennepin County judge issued arrest warrants Tuesday for a couple charged with failing to seek medical care for their gravely ill 7-year-old son before he died on a vomit-stained mattress in their Plymouth home.

Timothy D. Johnson, 39, and Sarah N. Johnson, 38, failed to show at their first court appearance Tuesday, one month after they were charged in Hennepin County District Court with gross misdemeanor child neglect in connection with the March 30, 2015, death of son Seth Johnson. The boy endured extensive trauma from an inflamed pancreas and possible infections until he died, according to the criminal complaints.

The Johnsons, who were not arrested when charged, were required to appear in court, but Assistant Hennepin County Attorney John Halla told Judge Gina Brandt that the two have moved to New Zealand.

Halla requested a new court date "in order to attempt international service on Mr. Johnson and his wife."

Brandt issued arrest warrants for the Johnsons but delayed executing them until Wednesday, when the court could receive more information from another prosecutor on attempts to reach the couple. Once the warrants are in effect, the Johnsons could be arrested and extradited to the United States.

Failed to seek help

Despite a yearlong review of evidence and consultations with a child abuse pediatrician, Hennepin County Attorney Mike Freeman said last month that Seth's illness and death could not be linked to the actions or inactions of the Johnsons. As a result, the Johnsons were charged with the most serious crime the law allows, he said.

According to the criminal complaint, Seth, who first joined the Johnson family through foster care and later was adopted, was severely underdeveloped physically and had numerous scrapes and bruises on his body at the time of his death.

In the weeks leading up to Seth's death, his parents said he stopped sleeping, would shake on occasion and developed blisters and other marks on his legs, along with lesions on his heels, which suggest a lack of mobility.

Neither parent offered law enforcement an explanation other than to say the boy was always hurting himself. They said he would throw himself down the stairs and hit his head.

They said they didn't want Seth on any medication and relied on their own research. They concluded Seth was suffering from post-traumatic stress disorder and from a traumatic brain injury. The Johnsons said Seth was a victim of fetal alcohol syndrome, but authorities found no record of such a diagnosis.

Despite Seth's mounting difficulties, they never sought medical attention for him. "They had 'issues with going to doctors,' " the charging documents quoted the Johnsons as conveying.

On the weekend before Seth's death, the boy was being watched by his 16-year-old brother while Sarah and Tim Johnson left town for a wedding. The teen called the parents on March 29, a Sunday, and said Seth wasn't eating or interacting. While under the teen's care that weekend, Seth stopped talking and couldn't get out of bed.

When the couple arrived home that Sunday night, Seth was on the floor and unresponsive. "They prayed for his health" at that moment, the complaint read.

They said they contemplated seeking medical care for Seth but decided to wait until morning to decide.

The next morning, Tim Johnson found Seth unresponsive on the mattress and covered in vomit. They cleaned him off and began CPR. Then they called 911.

Soon after Seth's death, the Johnsons went online, writing about how faith got them through their overwhelming grief. They also started a fundraising page that featured a photo of Seth, their "very quiet and hurting little boy."

They wrote that their "bright and beautiful boy died unexpectedly."

The Johnsons listed six surviving siblings while seeking $7,000 for funeral expenses and to help the family while Tim Johnson took a leave from work. Donations topped the goal by several hundred dollars.

Staff writer Paul Walsh contributed to this report.