A shooting inside Brigham and Women’s Hospital in Boston on Tuesday has left cardiac surgeon Dr. Michael Davidson dead. Davidson, 44, was shot inside the hospital’s Shapiro Center shortly after 11 a.m. The suspect, a Millbury man named Stephen Pasceri, 55, was found dead a short time later, apparently of self-inflicted gunshot wounds. Davidson was rushed to the emergency room with two gunshot injuries, but died late Tuesday night.

According to witnesses, Pasceri entered the hospital and asked for Dr. Davidson by name. Police said that Pasceri apparently shot the physician at some point during their meeting. Police say the shooting was targeted. Davidson treated Pasceri’s mother, who died Nov. 15.

Hospital staff had recently gone through training for active shooter situations, and a senior Boston law enforcement official said that the hospital’s response to the shooting was “textbook.” Staff members were asked to remain in place as the building was placed in a temporary lockdown, as were nearby subway and streets. Police officers conducted a room-by-room search and located Pasceri in an exam room with his weapon nearby. He was pronounced dead at the scene.

Police were on the scene within seconds of receiving the call of shots fired, and the area was secured within 15 minutes. A public address system inside the Shapiro Center announced that everyone needed to evacuate immediately, due to a life-threatening emergency on the second floor. Witness James Pittelli, whose son was a patient at the hospital, said there were police officers with weapons drawn yelling for everyone to get down.

Pittelli said it was a chaotic scene as people tried to get to safety, saying people were falling and knocking others over in a panic. One woman said they did not know what to think, and wondered if it was a terrorist attack.

A statement from the hospital said that Dr. Davidson was an inspiring surgeon who had devoted his career to “saving lives and improving the quality of life” for his patients. Pasceri’s family also released a statement, saying they are heartbroken by the tragedy, and offering sympathies to the doctor’s family and friends. Davidson was the Endovascular Cardiac Surgery director at Brigham and Women’s, and was also Harvard Medical School assistant professor.

Pasceri had a license to carry a firearm, obtained around 2010. The shooting occurred in the Carl J. and Ruth Shapiro Cardiovascular Center on the hospital’s second floor. Davidson was shot in a foyer between the examining area and the waiting room.

The hospital, which does not have metal detectors, will be evaluating its safety protocols, according to Betsy Nabel, hospital president. She said none of the city’s hospitals have them.