PORTLAND — Daimler Trucks North America agreed to pay $2.4 million to settle discrimination complaints filed by six minority workers who said they were subjected to threats and racial slurs at the company’s Portland plant.Brad Avakian, commissioner of the Oregon Bureau of Labor and Industries, announced the deal on Thursday. His office said the monetary settlement is easily the largest in the history of the agency’s Civil Rights Division. The investigation began last year and included interviews with 60 current and former employees.“We know that some of the incidents that were occurring stretched back over a decade, but the significant thing as well is that it was continuing right up until recent months,” he said. The complaints against the subsidiary of German automotive giant Daimler AG included an allegation that an employee threatened a black worker with a noose and said he’d drag the man behind a truck. Among other complaints, employees said they were called names such as “boy,” “buckwheat” and the N-word, and the company allowed intimidating graffiti, including a swastika, to remain in the bathroom.Meanwhile, a Native American worker said he faced harassment and his supervisor pushed him against a truck while challenging him to a fight. A black employee who is gay said he was repeatedly harassed because of his race and sexual orientation.