Eight people were injured, one of them seriously, in multiple crashes that involved nearly two dozen vehicles on southbound Interstate 5 and created a backup that at one point stretched for 10 miles.
Washington state troopers and tow trucks worked to clear the area and three southbound lanes had reopened by late Tuesday afternoon.
Kyle Ohashi with the Kent Fire Department says 20 vehicles were involved.
He says weather may have been a factor. He notes the often dangerous combination of rain, followed by a sunbreak and reflection on wet roads.
Several other Puget Sound-area freeway crashes were reported as sun mixed with occasional showers.
The Associated Press contributed to this report