Two men -- one in his 30s and the other in his 40s -- began fighting at the transit center just before 8 p.m. Police say one of the men pulled out a knife and stabbed the other man in the chest.
After the stabbing, police say a third man stepped in and punched the man with the knife. The blow was enough to knock the man off his feet, and police say he hit his head on the ground and fractured his skull.
Police and medics arrived moments later and both injured men were taken to Harborview Medical Center in Seattle. Police did not arrest the third man, but they are questioning him about the fight.