Yet another warning about Tamerlan Tsarnaev was apparently issued to US officials, this one just nine months before the Boston bombings. The alert that Tsarnaev had returned to the US after a seven-month-long trip to Russia was sent to a US Customs and Border Protection officer working on Boston's Joint Terrorism Task Force. But the Washington Post reports that it appears that official did not share the warning with anyone else on the task force, which included FBI agents who had prior contact with Tsarnaev.
The Post calls it a "significant, if slender, missed opportunity." That's because while the knowledge may have given the FBI fresh reason to question him, the tip wouldn't necessarily have led to that because it wasn't accompanied by new information that Tsarnaev posed a threat. The Post notes that it's possible the official did pass the information on to the FBI but just failed to document the move in a file.