BUFFALO, N.Y. — Police have cordoned off a Buffalo, N.Y., hospital where a woman was been fatally shot this morning.

A police official confirms that a woman was killed on the grounds of the Erie County Medical Center, which he describes as being in “complete lockdown” as SWAT teams and other officers cordon off the 65-acre campus.

The shooter remains at large.

Officials say the shooting occurred about 8:15 a.m. in a building that houses outpatient services and offices. The building is adjacent to the hospital’s main building.

Police aren’t allowing anyone in or out of the hospital. Incoming patients are being diverted to another hospital.

A police helicopter is circling over the medical center’s campus, which includes a 550-bed hospital.