A gunman has shot and killed a university cop at MIT. Boston Globe reports:

An MIT police officer was shot and killed Thursday night, according to the Middlesex district attorney’s office. The officer, who has not been identified, was shot multiple times, according to the district attorney’s office. No one else was hurt.

Police from multiple agencies were conducting a manhunt for the gunman across the school campus and on the T’s Red Line, according to authorities.

UPDATE at 10 PM: Holy crap. The manhunt on Twitter is at #MITShooting. Lots of people report explosions in Watertown, shots fired, and possibly grenades. The police scanner reports another officer is down.

UPDATE at 10:20 PM: CNN has been reporting on TV that one or two suspects are in custody, there have been reports of several explosions, and there are possibly undetonated explosives. But take all this news with a boulder of salt. There is also lot of chatter and speculation on Twitter that there is some link between this manhunt and the marathon bombing, but until we're given confirmation, all that chatter is unconfirmed.

It's unknown if this police action in Watertown is linked to MIT shooting or the bombings.

UPDATE at 11 PM: The hashtag #boston seems best for updates. It appears way ahead of cable news, but it's also chock full of unconfirmed bullshit.