An "officer-involved shooting investigation" has been launched after a suspected gunman's death at a Portland, Ore., hospital.

Officers were called to the Adventist Medical Center in south-east Portland at 9:30 p.m. Sunday local time (0:30 a.m. ET Monday) following reports of a man with a gun on the hospital's grounds, city police spokesman Pete Simpson said in a statement.

Police encountered the suspect as they locked-down the hospital and its campus, according to Simpson.

“Shots were fired and the suspect is deceased,” the statement said. “Portland Police are now in the very early stages of an officer-involved shooting investigation.”

Judy Leach, spokeswoman for the Adventist Medical Center, said the hospital “issued a code silver as a result of a combative person on the premises.”

She added: “There were no injuries to any patients or staff. The suspect is officially deceased. Portland Police continue to investigate the incident.

“The health, security, and safety of our patients, physicians, and staff is our number one priority. The policy put into place worked. Counselors and chaplains are on hand for anyone requiring services.”