A man has been rescued after being stuck in an abandoned restaurant's grease vent for two days.

The man, who was physically exhausted and suffering from dehydration, likely "would not have survived another day given the circumstances," Alameda County Sheriff's Office said in a Facebook post.

Sheriff's officers and the Alameda County Fire Department were called to a disused Chinese restaurant in San Lorenzo, around 25 miles east of San Francisco, to reports of a "faint voice calling for help," at around 9.30am on Wednesday, Sergeant Ray Kelly said.

Image: It was unclear how the man got in to the vent. Pic: Alameda County Sheriff's Office

Realising the sound was coming from a roof vent on top of the restaurant, they used a ladder and found the suspect stuck in a sheet metal grease duct running from the roof to the kitchen.

The man, 29, was covered in grease and oil and was trapped in such a position that he could not escape from the chute, which narrowed considerably near the bottom where it opened on to the stove.


Image: The man was physically exhausted dehydrated. Pic: Alameda County Sheriff's Office

Pictures released by the sheriff's office showed his feet jammed up against a tiny opening into the restaurant's kitchen.

It took firefighters between 30 minutes and an hour to free the man, who has not been named.

Image: He was unable to pull himself out of the vent. Pic: Alameda County Sheriff's Office

He told officials he had been stuck for two days and, despite being exposed to the cold and the elements, was in generally good condition, Sgt Kelly said.

He was taken to a local hospital for treatment and is expected to make a full recovery.

The sheriff's office has opened a trespassing and vandalism investigation, but said it did not know if the man was trying to break in to the restauraunt.

The extraction caused about $10,000 (£7,900) worth of damage to the ventilation system, Sgt Kelly said.

"It's not the first time I've seen this," he told the San Francisco Chronicle.

"We are very thankful to our citizen reporter and our firefighters for saving this man. It is likely he would not have survived another day given the circumstances. The suspect is expected to make a full recovery," he added.