This comes as residents of the town of Watertown, Massachusetts -- have been ordered to stay indoors. There were multiple reports of gunfire and explosions in that suburban Boston town.
According to investigators, one suspect was shot and taken to the hospital, another suspect is reported to be on the loose. In addition to local police -- FBI agents are also on the scene.
Investigators say it is connected to an incident earlier Thursday night in the town of Cambridge, Massachusetts. That's where a Massachusetts Institute of Technology police officer was shot to death on campus. Police say the officer was assisting in the search for a suspect and was shot several times.
MIT posted a message on its website advising students to stay inside as the situation was "very active."