TOPEKA, Kan. (AP) — The operator of a pipeline with the largest onshore crude oil spill in nine years has reopened all of it except for the stretch in Kansas and northern Oklahoma that includes the site of the rupture.

Canada-based T.C. Energy said in a statement Wednesday night that its Keystone system has restarted operations from Canada to southern Nebraska and from there to south-central Illinois. It also is operating the pipeline from northern Oklahoma to the Gulf Coast.

The Dec. 7 spill forced the company to shut down the Keystone system and dumped about 14,000 barrels of heavy crude oil...