BROOKLYN - The New York Blood Center has declared a blood shortage emergency.

Officials at the center say they ideally like to always have a seven- to 10-day blood supply in reserve, but right now they have an all-time low of one to two days.

All blood types are needed, but staff members say O negative, A negative, and AB blood types are in high demand. 

The center says it will be deploying mobile donation vans to make it easier to receive blood donations. 

The center is requesting that groups and organizations host blood drives.