The driver reportedly lost control when the truck blew a tire sometime before 4 a.m. while merging from Interstate 405 to northbound Interstate 5. Washington state police said the truck spilled 448 bee hives on the roadway. Many of the bees were killed in the accident.
Crews were working to clear the accident and beekeepers were on the scene, as well. The bees remained calm at first, but they grew increasingly agitated as temperatures rose after sunrise.
Officials said removal of the bees could take hours.
The truck driver was not hurt.