The victim suffered only a minor cut to their arm.
Mount Vernon Police are investigating the origin of the improvised explosive device.
The incident occurred at the WTA Bus Station on Cordata Parkway earlier this month.
36-year-old Alexander Vanags and 67-year-old Lynda Mercy are each facing second degree murder charges.
The 32-year-old suspect is being held at the Whatcom County Jail on $1 million bail.
A WSDOT crewmember spotted the suspect near Gages Slough, where he was “forced” into custody by several law enforcement agencies.
Both could face a at least ten years in prison.
The cause of the fire and warning remains unknown.
The woman was arrested in January 2025 and is expected to go to trial in March.
Authorities say the employee conducted unauthorized searches within a restricted system.