Southbound Interstate 405 near Sunset Boulevard Northeast was blocked for about three hours Friday morning after a tractor-trailer involved in an accident lost about 15 gallons of fuel, according to the Washington State Patrol.

The tractor-trailer was southbound near Sunset at about 9:30 a.m. when traffic came to a stop; the rig struck a box truck, according to the state patrol, and then hit the right-side freeway barrier.

The tractor-trailer lost 10 to 15 gallons of fuel that stayed on the roadway.

The state patrol is investigating and will determine whether to cite the driver, a 55-year-old Everett man.