The walking dead have infiltrated the Energy Department.
Energy Secretary Steven Chu shared a picture of himself as a zombie on his Facebook page in an effort to teach users about saving electricity.
"To date, there is no scientific evidence about the existence of zombies, but what about vampires?" Chu asked in a Facebook note.
He went on to warn readers about so called "vampire appliances," such as computers, stereos and DVD players, which use power in standby mode.
Chu said these types of appliances could increase a household's monthly electricity bills by at least 10 percent. To ward off these particular vampires, Chu suggested using power strips, which make it easier to turn off a cluster of unused equipment, and putting computers into sleep mode.
A member of Chu's staff found the zombified photo of Chu on a technology blog and forwarded it to him, said department spokesman Dan Leistikow.
"As a lifelong geek, I've never had such a cool Halloween costume," Chu wrote on Facebook.
He is an active Facebook user with more than 14,500 followers. Recent posts include his thoughts on the film "The Social Network," a question-and-answer session about home energy efficiency and a video tribute to his high school physics teacher.
"He sees Facebook as an extremely valuable tool to speak to people directly," Leistikow said.