A multi-vehicle crash involving three cars and a semitruck shut down three northbound lanes of Interstate 5 in Seattle on Tuesday afternoon, October 20, 2026, and spilled a large amount of diesel across the freeway, according to The Seattle Times and FOX 13 Seattle.

The crash happened shortly before 3 p.m. on northbound I-5 near South Michigan Street in South Seattle, The Seattle Times reported. The semitruck's fuel tank was punctured in the collision and spilled around 300 gallons of diesel onto the roadway. FOX 13 Seattle reported that multiple lanes were blocked by the crash and published a Washington State Department of Transportation photo showing the blocked lanes in South Seattle on Tuesday.

Interstate 5 is Seattle's main north-south freight and commuter corridor, and lane closures near Michigan Street affect traffic across the south end of the city, including routes toward the port and the airport. The initial reports did not include an official statement on injuries or on what caused the four vehicles to collide, and drivers were left to work around the blocked northbound lanes while the spill was dealt with.

No names were released in the initial reporting. Awaaz Punjab will update this story if the Washington State Patrol or WSDOT releases injury or cause information. Sources: The Seattle Times, October 20, 2026; FOX 13 Seattle, October 20, 2026 (photo: WSDOT).