UPDATE: As of 12:40 p.m., the freeway was opened in Olympia, according to the state Department of Transportation.
Southbound is slow from Martin Way and southbound 101 is backed up from Black Lake Boulevard. Northbound from Tacoma is also affected.
ORIGINAL: According to dispatchers and Olympian reports, all lanes of Interstate 5 south in Olympia are blocked at milepost 105.
A semitrailer appears to have jackknifed and other vehicles might be involved.