As the search for the person of interest in a fatal shooting at ECMC Wednesday expands to a nationwide manhunt, Buffalo Police Commissioner Daniel Derenda says he's certain that Doctor Timothy Jorden is still in the United States. In a Thursday morning briefing with reporters, Derenda added that he doesn't know if Jorden is still alive.

Jorden remains a person of interest who is wanted for questioning in the shooting of Jacqueline Wisnewski, 33.

Buffalo police are working with state, local, and federal law enforcement agencies, including the FBI and U.S. Marshals.

Derenda stated that law enforcement will need to be careful when approaching the trauma surgeon, because he is an army veteran specially trained in the use of weapons. Still, the police commissioner said, he didn't believe the general public was in danger.

"I don't believe he's a general threat to the public. This was a targeted incident, this was not a random act, but he should be considered armed and dangerous at this point."

Meanwhile, Derenda confirmed Buffalo Police Officer Martin Motley III is under police investigation after he was seen leaving Jorden's home with $5,000 cash, a gun, and an expensive watch just hours after Wednesday’s fatal shooting of Wisniewski.