WUHAN, May 6 -- No casualties have been reported from a fire at a high-rise office building on Tuesday in central China's Hubei Province, according to fire authorities.

Firefighters have extinguished the blaze that broke out at around 10:30 a.m. in the East Lake High-tech Development Zone in the provincial capital city of Wuhan, the authorities said.

An initial investigation found that the cooling tower of the central air conditioning unit on the building's roof caught fire, but did not spread downward.