Authorities confirmed that someone was taken into custody shortly before 3 p.m. following reports of an active shooter at Dartmouth-Hitchcock Medical Center. The hospital was under lockdown and it wasn't clear if that was lifted.
Rhode Island State Police said the suspect's car had Rhode Island plates so police in New Hampshire reached out to the state's Fusion Center, an information center under the command of the state police that also involves representatives from local, state and federal agencies.
The center helped identify the suspect as a Rhode Island resident, said Laura Meade Kirk, a state police spokeswoman. The resident's name wasn't immediately released.
People were told to avoid the area around the hospital, and traffic was stopped on a route leading to the medical center.
The Bureau of Alcohol, Tobacco, Firearms and Explosives and Vermont State Police assisted New Hampshire and local police.
WCAX-TV reports an employee said all workers received an email from the hospital about a "code silver," telling them to get out if possible and otherwise to shelter in place. "Code silver" indicates that a violent situation is unfolding.
The state attorney general's office is investigating.