SAN LORENZO, CA - First responders on Wednesday rescued a trespasser — possibly a burglar — who was reportedly trapped for about two days in a grimy vent at a vacant Chinese restaurant in San Lorenzo, according to officials.

The 29-year-old man, seen caked in grease as he was stuck in the narrow passageway, was freed from the vent and taken into custody, Alameda County Sheriff's officials said.

Fire units were initially dispatched after receiving word from a neighboring business that someone was yelling from the restaurant, officials said.

As firefighters arrived at the scene along the 700 block of Bockman Road after receiving a report moaning sounds heard from inside the restaurant. They eventually found the man who told them he had been stuck in the duct system above the stove for about two days.

Crews managed to free him in about 30 minutes, according to officials. The man did not suffer any serious injuries, but he was said to be suffering from fatigue, body cramps and pain in his extremities.

He was transported via ambulance to a local hospital for treatment, according to Alameda County Sheriff's Office.

"At this time, we are conducting a trespassing and vandalism investigation. It is unknown if the suspect intended to commit a burglary," the sheriff's office said in a statement.

"It is likely he wound not have survived another day given the circumstances. The suspect is expected to make a full recovery," the statement read.