EVERETT, Wash. -- An 11-year-old boy is in serious condition at Seattle's Harborview Medical Center, and a 16-year-old relative is under arrest, after the boy was struck by gunfire near the 12400 block of Admiralty Way in south Everett.



Police arrested a 16 year old male relative in connection to the shooting; the 16 year old is a relative to the victim, the Snohomish Sheriff's office reported.



Snohomish County deputies are still in the early stages of the investigation and are working to determine exactly what happened.



Witnesses told detectives someone ran away from the scene after the shot was fired.



Upon further investigation, deputies learned the boy may have been shot by an older sibling by accident.



The 16 year old arrested has been booked into the Denny Youth Center for investigation of Reckless Endangerment and Unlawful Possession of a Firearm, police reported. No charges have been filed.



The case is being investigated by the Major Crimes Unit, and more details will be released as they become available.



There is no additional danger to the public, deputies said.



This is a developing story and will be updated.