This latest incident unfolded about 9 a.m. at the Benning Road station, which is on the Silver and Blue Lines of the Washington Metropolitan Area Transit Authority system, police said.It was not clear what led to the gunfire, but transit police described the victims as a boy, a woman and a teen male.This latest incident comes after an off-duty FBI agent fatally shot a person following a dispute inside the bustling downtown Metro Center station early Wednesday evening.The agent got into an altercation with another person on the train platform just after 6:20 p.m., said Ashan Benedict, the executive assistant chief of police for the Metropolitan Police Department.During the argument, one of the individuals grabbed the other and they both fell down an 8-foot drop over a side wall, located away from the train tracks at the end of the platform, and continued to struggle, police said."