KING COUNTY, WA (KPTV) – Two kids in Washington have been diagnosed with a rare condition believed to be linked to COVID-19, marking the first cases reported in the state, according to state health officials.

One patient is from Snohomish County and the other is from King County, according to health officials.

Both are being treated at Seattle Children’s Hospital.

Health officials say little is known about pediatric multi-system inflammatory syndrome.

One of the patients in Washington state is under the age of 10 and the other is between 10 and 19 years of age, health officials said.

“While the vast majority of children appear to have mild or asymptomatic infection, it’s important to remember that—although rare—some children can develop serious complications like these,” Chris Spitters, health officer for the Snohomish Health District, said.

“Our thoughts are with the young patient, their family and the care team at Seattle Children’s, and we wish for a speedy recovery.”.

Health officials in Washington did not release any additional information about the cases due to privacy concerns.

Health officials said she was treated at Randall Children’s Hospital at Legacy Emanuel in Portland.