An unknown illness is sickening and killing Southern California sea gulls, a bird rescue organization said on Tuesday.

LOS ANGELES - An unknown illness is sickening and killing Western gulls along the shores of Southern California. Affected gulls have been found along the coast from Malibu to Redondo Beach, according to the International Bird Rescue. Some have been found dead on beaches.

Loved ones are searching for a Southern California man who has been missing for nearly two weeks. Donald Banks, 64, was reported missing on July 27, according to the Los Angeles County Sheriff’s Department.

An unknown illness is killing western seagulls in Southern California. State and county agencies are looking into what's causing the illness.