Cops probing Sydney CBD garage blaze

A fire in a garage behind an inner Sydney building raged for more than two hours before being extinguished.

Emergency services were called to the blaze at the rear of a multi-storey building on George St, in Haymarket, about 11.30pm on Thursday.

Firefighters put out the fire about two and a half hours later, with the blaze damaging the garage, and destroying the furniture and mattresses stored in it.

Detectives are still trying to work out the cause of the fire with Fire and Rescue NSW officers unable get into the garage as it is structurally unsound.