A shooting incident at a medical center in Florida has left two people dead, officials say.

The shooting happened on the third floor of the Parrish Medical Center in Titusville at 2 a.m. local time on Sunday.

The gunman fatally shot an elderly female patient and a female hospital employee, police said.

Police said that the suspect is in custody, but the motive behind the shooting is not known yet.

According to the US Centers for Disease Control and Prevention (CDC), firearms are the cause of death for more than 33,000 people in the United States every year, a number that includes accidental discharge, murder, and suicides.

There are about 270 million to 300 million guns in the US, about one per person, data show.