Roll up a sleeve for New Yorkers in need. The New York Blood Center is putting out an urgent call for donations.

The center has declared a blood emergency, saying supplies have fallen below the seven-day supply considered necessary for a safe inventory.

Supplies are at critically low levels for blood types B negative, A negative, and the universal donor O negative.

Multiple blood drives are taking place in the city today.

To find one near you, visit the Blood Center's website.