A black civil rights activist has infiltrated a Detroit-based neo-Nazi group and plans to destroy it from the inside.Rev. James Hart Stern replaced Jeff Schoep as leader of the National Socialist Movement in January and wants to use the position to sabotage a lawsuit filed against the extremist group, according to court documents filed Thursday in a federal court in Virginia.The suit was filed over the group’s involvement in the violence that broke out at a 2017 white nationalist rally in Charlottesville, Va.Stern is asking the court to issue a judgment against the group, which the Southern Poverty Law Center described as “one of the largest explicitly Hitlerite groups in America.”“It is the decision of the National Socialist Movement to plead liable to all causes of actions listed in the complaint against it,” Stern wrote.How Stern managed to infiltrate the NSM remains a mystery.Neither he nor Schoep returned calls for comment.Matthew Heimbach, a white nationalist and former outreach director for NSM, told the Associated Press that Schoep, who had been living in Eastpointe, clashed with rank-and-file members over its direction.In 1994, Schoep took over the group at the age of 21 and renamed it the National Socialist Movement, according to the Southern Poverty Law Center.“I think it’s kind of a sad obit for one of the longest-running white nationalist organizations,” Heimbach told theWhile Heimbach said the group had about 40 active members, its rallies drew much larger crowds, like in Toledo in 2005, when people in full Nazi uniforms triggered a riot.NSM also played a role in attracting white supremacists to Charlottesville, where the rally sparked bloodshed.For decades, Schoep has been on the radar of the Southern Poverty Law Center, which tracks hate crimes and groups.According to NSM’s website, Schoep said the group’s goal is to purge all non-white people from America.“All non-White immigration must be prevented,” Schoep wrote. “We demand that all non-Whites currently residing in America be required to leave the nation forthwith and return to their land of origin: peacefully or by force.”