Police and federal agents in Boston shot and killed a man earlier today after he waved a large military-style knife at officers, and sources are now reporting that he was part of a broader terror investigation involving suspected Islamist extremists being tracked by the U.S. Joint Terrorism Task Force, and belonged to an ad hoc terror network. The suspect was identified as Usaama Rahim, according to his brother, Ibrahim Rahim, who posted about the death on Facebook. In his post, he wrote that his brother was shot three times in the back, and that he was on the phone with their father. A Boston police officer as well as a federal agent both opened fire, and the shooting is under investigation.