The suspect was taken into custody trying to flee, pulled from a auto not far from the hospital's sprawling campus. The investigation is ongoing, and the hospital has returned to normal operations.
Travis Frink is charged with first-degree murder in the death of his mother, 70-year-old Pamela Ferriere.
"You became very creative over the hours...one team set up a MASH unit in the parking lot and saw over 40 patients, removed stitches, changed dressings and scheduled those patients to return later this week for follow-up", she wrote. After several shots were fired, Frink walked out of the room without saying anything, Ferriere told police.
The hospital issued a "code silver" alert to employees, which orders people who can safely flee to do so, and the rest should shelter in place. The DHMC alert said police were looking for a 6-foot 1-inch male with salt-and-pepper blond hair and wearing a red camouflage shirt.
It took Frink a total of nine minutes - from the moment he signed in at the visitors desk to the time he arrived at the ICU unit - for him to take his mother's life, MacDonald said.
During his arraignment at Grafton County Superior Court in North Haverhill on Wednesday, Frink said nothing.
Dartmouth College, situated around two miles far from the healing center, tweeted that its grounds was not on lockdown. An image taken inside the hospital showed SWAT team members accompanying staff as they swept the building.
"Today was an incredibly stressful day, and a tragic day for the affected family. we had the best outcome possible, however", she said.
"I can speak for all of law enforcement from this state and the New England region that we are prepared and we are ready to handle such a situation", said New Hampshire State Police Col. Chris Wagner.
More than 100 first responders attended to the area.