"At this point we are treating this case as a murder-suicide," Bealefeld said.
Police identified the mother as Jean Davis, age 84, and her son as Paul Warren Pardus, age 50, of Arlington, Virginia. Pardus had no prior criminal record beyond traffic violations, police spokesman Anthony Guglielmi said.
The doctor, whose name was not released, was rushed to surgery for an abdominal wound and is expected to survive, Guglielmi said.
"He's in the best place he could ever be," Guglielmi said, referring to the hospital.
Bealefeld initially identified the gunman as Warren Davis. Hospital officials said they could not disclose any details about what illness afflicted the gunman's mother, citing federal privacy laws.
Johns Hopkins Hospital, which first opened in 1889, is part of a $5 billion medical system, according to its website. The 982-bed facility has consistently earned the top spot in U.S. News & World Report's annual rankings of more than 4,800 American hospitals, placing first in five medical specialties, among other things.
Harry Koffenberger, the hospital's security chief, said the roughly 80,000 visitors who come to the hospital each week are issued wristbands. Only "high-risk" patients get screened with hand-held magnetometers, he said.
"We have over 80 doors, loading docks and emergency exits on these campus buildings," Koffenberger said. "So to put a magnetometer at 80 doors, and the required armed force that would need to be staffing the magnetometers, is not realistic."
Authorities evacuated part of the hospital after the shooting, and Bealefeld said the facility's security plan "worked as designed" to protect patients, staff and visitors. The hospital "asked employees, visitors, patients and caregivers to stay in rooms or offices until further notice" restricted access to the main hospital building after the shooting, it said in a statement.
Earlier, police said officers shot and killed the gunman, but later said that account was incorrect.
A man shot a faculty physician as well as his own mother before killing himself at  in Baltimore, Maryland. The shooting occurred on the eighth floor of the Nelson Building, the hospital's main building. Baltimore police found the suspected shooter, who had been barricaded inside his mother's hospital room for several hours before killing himself and his mother.

At around 11:15 a.m.  (1515 ), an unnamed doctor was shot in the chest at a patient area of the Nelson Building's thoracic center. All major hospital facilities were placed under a lockdown, and some medical personnel were evacuated from the Nelson Building. The doctor was sent to surgery at the hospital, and police spokesperson Anthony Guglielmi said that the doctor will likely survive the incident. He was not aware of any connections between the suspect and the doctor, who was in critical condition.

A nurse at the hospital told '''' that the shooter was dissatisfied with how his mother had been treated and even said that he was going to jump out of a window. The nurse said that, upon hearing gunshots, she ran.

Earlier, Baltimore area police said that they were "in the process of a tactical operation" to capture the gunman, who was holed up on the eighth floor. A spokesperson for the  (FBI) said that it had been assisting local police in the incident. A Johns Hopkins spokesperson had previously said that authorities had taken the shooter into custody, but police said that the report was incorrect.

The suspect, who had not taken any hostages, was described as a black man in his thirties. After a standoff lasting for three hours, law enforcement officers moved into his mother's hospital room, and found both him and his mother dead from gunshot wounds to their heads. The suspect was first identified as 50-year-old Warren Davis, and his mother as Jean Davis. Police later said that "Warren Davis" was an alias and that his real name was not known.

Baltimore Police Commissioner Frederick Bealefeld, who said that the department is "treating this case as a murder-suicide," said that no officers reported hearing the shots that killed the two.  Police had previously said that the gunman had been shot and killed by police, but police later said that that report was incorrect.