A police officer for the Massachusetts Institute of Technology was shot to death on Thursday night at the school's Cambridge campus, authorities said, adding no suspects were in custody.
MIT police were investigating the shooting and had issued a campus-wide emergency alert. Massachusetts State Police and Cambridge police said they were assisting in the investigation.
The shots "were reported near Building 32 ... which is currently surrounded by responding agencies," MIT said in an emergency statement warning students to "stay indoors and away from the area."
"Responding agencies continue to investigate the situation," MIT said on its website. "Police are sweeping the campus at this time, please continue to stay indoors and remain inside until further notice."
MIT police representatives could not be reached immediately for comment.