A San Francisco couple was not expecting to be wakened and attacked by a naked intruder who broke into their house early Sunday morning. 

The unnamed, nude suspect was going rooftop-to-rooftop down Brighton Avenue before breaking in the window of the victim's house, reports CBS San Francisco.

The homeowner confronted the suspect, causing the suspect to bite him on the shoulder. The suspect proceeded to go into the homeowner's bed and bite his wife on the leg.

"He was crazy," Stephen Wong, an eyewitness, tells CBS San Francisco. "I saw them take a guy out on a stretcher and put him in an ambulance." 

When authorities arrived several witnesses told CBS San Francisco the suspect was screaming loudly and was restrained to a gurney. 

The investigation is ongoing.