Miami, Florida (CNN) -- A former employee who had recently been fired from Palm Bay Hospital returned there Thursday afternoon carrying a gun, holed himself up in an office, then apparently killed himself, officials said.
The incident began about 2:20 p.m., when Palm Bay police got a call from people in the hospital cafeteria who said a man was pointing the gun at anyone who tried to talk to him, said police spokeswoman Yvonne Martinez.
"Initially, when he came into the hospital waving the gun, anybody that attempted to make contact with him or communicate with him he just dismissed and pointed the gun at them," she said. "Clearly, he appeared to be on a mission."
Earlier she had said that, during the police response, "we were told that shots had been fired," but "nobody was injured." But she later told reporters that those shots may have been the gunman taking his own life.
As police officers and SWAT personnel from Palm Bay and nearby agencies assembled outside the hospital, the hospital was locked down and emergency vehicles were diverted to other hospitals.
A few hours later, a robot found the man's body inside an administrative office near the cafeteria's food-preparation area.
Martinez said the man had had "issues" with the property manager, was distraught and "had made some threats as to suicide."
Hospital spokesman Elliot Cohen told CNN that the man, who has not been identified publicly, "was terminated about a month ago for having a poor attendance record" after having worked at the hospital for about two years.
He would not divulge the man's position.
Palm Bay Hospital resumed normal operations as soon as the body was discovered, he said.
CNN's Vivian Kuo contributed to this story.