(WSB Radio) -- The American Red Cross is issuing an urgent plea to metro Atlantans to donate blood.

Canice Gulden, communications director for the southern region, tells WSB's Sandra Parrish the most urgent need for types O and B.

"We are in a critical situation with types O and B and have very little of those blood types in the state," she says.

Gulden says in some cases they've had to turn down blood requests from hospitals.

Besides the seven donation centers in metro Atlanta, special drives are being held through Wednesday at five metro area malls including Town Center, Northlake, Cumberland, Gwinnett Place, and Mall of Georgia.